My laptop has become slower, the fans are louder

i've got a laptop running on Ubuntu 22.04, an RTX 2060 mobile, an intel core i7-9750h cpu, 16gb of ram, a 512gb ssd, which means I shouldn't have much trouble using firefox or other software, but I noticed that, since a few days, my laptop has become much slower than usual, with the system having trouble to keep up with any demanding software like Krita, or even steam games which run very poorly now, and my fans are also way louder than usual (which is weird, because the computer isn't particularly hot or running any intensive program it seems, and the cpu and gpu temperature is low) even when nothing is running except for background processes. Even though my cpu doesn't seem to be used more or less than usual, and same for the gpu and the memory. Could it be a hardware issue too ? and if so, how to verify it ?

Here is the cpu and memory usage if needed

top - 17:38:43 up 50 min,  1 user,  load average: 2,16, 2,75, 1,95
Tâches: 352 total,   2 en cours, 350 en veille,   0 arrêté,   0 zombie
%Cpu(s):  2,7 ut,  1,4 sy,  0,1 ni, 95,7 id,  0,1 wa,  0,0 hi,  0,0 si,  0,0 st
MiB Mem :  15813,5 total,   8101,3 libr,   3440,9 util,   4271,3 tamp/cache
MiB Éch:  16384,0 total,  16384,0 libr,      0,0 util.  11587,1 dispo Mem 
PID UTIL.     PR  NI    VIRT    RES    SHR S  %CPU  %MEM    TEMPS+ COM.                                                                                                                                                                   
10553 mario     20   0   11,6g 497456 232016 S  13,6   3,1  10:31.53 firefox                                                                                                                                                                
10741 mario     20   0 2494868 124352  94212 S  11,6   0,8   2:21.99 Privileged Cont                                                                                                                                                        
 3550 mario     20   0   25,9g 143500  94700 R   8,3   0,9   2:05.96 Xorg                                                                                                                                                                   
 3931 mario     20   0 5915928 314624 138860 S   7,6   1,9   2:19.45 gnome-shell                                                                                                                                                            
14484 mario     20   0 2557192 159208  96952 S   3,3   1,0   0:10.37 Isolated Web Co                                                                                                                                                        
 2724 netdata   39  19  137732   9596   4244 S   2,7   0,1   1:27.93 apps.plugin                                                                                                                                                            
14861 mario     20   0  691392  52532  39076 S   2,3   0,3   0:00.58 gnome-terminal-                                                                                                                                                        
 2336 netdata   39  19 1138928 109208   8908 S   1,7   0,7   1:40.21 netdata                                                                                                                                                                
  277 root     -51   0       0      0      0 S   1,3   0,0   0:10.97 irq/51-DELL08EA:00                                                                                                                                                     
13490 mario     20   0 3017576 342564 122112 S   1,3   2,1   3:08.75 Isolated Web Co                                                                                                                                                        
 2722 netdata   39  19   71484  44344  15616 S   1,0   0,3   0:33.61 python3                                                                                                                                                                
 2734 netdata   39  19  775388  50688  36060 S   0,7   0,3   0:16.28 go.d.plugin                                                                                                                                                            
14719 mario     20   0 2443040  81080  63428 S   0,7   0,5   0:00.22 Isolated Servic                                                                                                                                                        
14889 mario     20   0   16172   4380   3480 R   0,7   0,0   0:00.05 top                                                                                                                                                                    
   14 root      20   0       0      0      0 I   0,3   0,0   0:04.28 rcu_preempt                                                                                                                                                            
   34 root      20   0       0      0      0 S   0,3   0,0   0:02.25 ksoftirqd/3                                                                                                                                                            
  728 systemd+  20   0   14828   6184   5388 S   0,3   0,0   0:05.53 systemd-oomd                                                                                                                                                           
  926 root      20   0  264892  20200  16360 S   0,3   0,1   0:02.02 NetworkManager                                                                                                                                                         
 3871 mario     20   0  162752   8004   7208 S   0,3   0,0   0:00.55 at-spi2-registr                                                                                                                                                        
 3885 mario     20   0  444036  57324  46392 S   0,3   0,4   0:00.77 xdg-desktop-por                                                                                                                                                        
10785 mario     20   0 2848564 288512 110828 S   0,3   1,8   0:23.23 Isolated Web Co                                                                                                                                                        
12048 root      20   0       0      0      0 I   0,3   0,0   0:00.28 kworker/4:0-mm_percpu_wq                                                                                                                                               
12458 root       0 -20       0      0      0 D   0,3   0,0   0:04.00 kworker/u25:2+i915_flip                                                                                                                                                
14792 root      20   0       0      0      0 I   0,3   0,0   0:00.25 kworker/3:2-events                                                                                                                                                     
    1 root      20   0  167556  12752   8256 S   0,0   0,1   0:03.71 systemd                                                                                                                                                                
    2 root      20   0       0      0      0 S   0,0   0,0   0:00.01 kthreadd                                                                                                                                                               
    3 root       0 -20       0      0      0 I   0,0   0,0   0:00.00 rcu_gp                                                                                                                                                                 
    4 root       0 -20       0      0      0 I   0,0   0,0   0:00.00 rcu_par_gp                                                                                                                                                             
    5 root       0 -20       0      0      0 I   0,0   0,0   0:00.00 netns                                                                                                                                                                  
    7 root       0 -20       0      0      0 I   0,0   0,0   0:00.00 kworker/0:0H-events_highpri                                                                                                                                            
    9 root       0 -20       0      0      0 I   0,0   0,0   0:00.00 mm_percpu_wq                                                                                                                                                           
   10 root      20   0       0      0      0 I   0,0   0,0   0:00.00 rcu_tasks_kthread                                                                                                                                                      
   11 root      20   0       0      0      0 I   0,0   0,0   0:00.00 rcu_tasks_rude_kthread                                                                                                                                                 
 12 root      20   0       0      0      0 I   0,0   0,0   0:00.00 rcu_tasks_trace_kthread                                                                                                                                                
   13 root      20   0       0      0      0 S   0,0   0,0   0:00.15 ksoftirqd/0                                                                                                                                                            
   15 root      rt   0       0      0      0 S   0,0   0,0   0:00.01 migration/0                                                                                                                                                            
   16 root     -51   0       0      0      0 S   0,0   0,0   0:00.00 idle_inject/0                                                                                                                                                          
   18 root      20   0       0      0      0 S   0,0   0,0   0:00.00 cpuhp/0                                                                                                                                                                
   19 root      20   0       0      0      0 S   0,0   0,0   0:00.00 cpuhp/1                                                                                                                                                                
   20 root     -51   0       0      0      0 S   0,0   0,0   0:00.00 idle_inject/1                                                                                                                                                          
   21 root      rt   0       0      0      0 S   0,0   0,0   0:00.15 migration/1                                                                                                                                                            
   22 root      20   0       0      0      0 S   0,0   0,0   0:00.21 ksoftirqd/1                                                                                                                                                            
   24 root       0 -20       0      0      0 I   0,0   0,0   0:00.00 kworker/1:0H-events_highpri                                                                                                                                            
   25 root      20   0       0      0      0 S   0,0   0,0   0:00.00 cpuhp/2                                                                                                                                                                
   26 root     -51   0       0      0      0 S   0,0   0,0   0:00.00 idle_inject/2                                                                                                                                                          
   27 root      rt   0       0      0      0 S   0,0   0,0   0:00.16 migration/2                                                                                                                                                            
   28 root      20   0       0      0      0 S   0,0   0,0   0:00.14 ksoftirqd/2                                                                                                                                                            
   30 root       0 -20       0      0      0 I   0,0   0,0   0:00.00 kworker/2:0H-events_highpri                                                                                                                                            
   31 root      20   0       0      0      0 S   0,0   0,0   0:00.00 cpuhp/3                                                                                                                                                                
   32 root     -51   0       0      0      0 S   0,0   0,0   0:00.00 idle_inject/3                                                                                                                                                          
   33 root      rt   0       0      0      0 S   0,0   0,0   0:00.16 migration/3                                                                                                                                                            
   36 root       0 -20       0      0      0 I   0,0   0,0   0:00.00 kworker/3:0H-events_highpri                                                                                                                                            

Phase 1: I regularly do these three tasks before touching the OS and tweaking it.

1. I do this once every 4 months. Remove the back cover the laptop and vacuum the fan vent (copper pipe), around the heat sink and use the air duster around the processor.
2. Once an year I unscrew the heatsink/copper vent connected to fan and apply fresh silver paste after cleaning off the old stuff off the processor.
3. Anytime I use, I ensure that its not kept on carpet or lap and operated. I ensure that the ventilation ducts are not closed.

Coming to the loud sound of the fan: Based on the configuration its not a super old laptop. Please check if there are any spurious plugins that you might have installed on browser.

Lastly: I have a similar if not identical configuration on a Latitude E7450 and I run Java, JDK 19, Compatible Eclipse/ Ursina Game Engine, VSC Editor, MySQL DB all running simultaneously and of course about 30 tabs of Firefox. No issues so far. I might suggest you one option though outside of ps -kill command and that is: Keep the laptop in inverted "V" position, connect it to external monitor, keyboard, mouse and try using for a few days without any changes. We can rule out overheating, ventilation and dust accumulation problem. I'll check for other options for you in the meantime.

On an afterthought: I had a Vostro 1400 that I purchased in 2007. Until 2021 it worked faithfully with a Ubuntu 18.04 LTS on it. Suddenly it started making lot of noise and when I got it checked by a good repair team the confirmed that the motherboard <-- --> power socket <-- --> relay is/was damaged. I had to discard it. Suggest you get this checked by organizations that offer you one free consultation.

Thanks, B