NGINX Block traffic to my home IP (default new website page or first subdomain), requiring a valid domain name hosted at home

My goal: disable/drop traffic to just home IP without domain in request.

Issue: Currently, if I (or anyone else) accesses my home IP via HTTP or HTTPS, it will show the first subdomain that is configured as a virtual host. I have tried multiple different configurations to drop or show my home IP "domain" as 410 Gone or even 444 drop connection, without success.

Here is the default server block in /etc/nginx/sites-available/default

    # Default server configuration
#
server {
        #server_name _;

        listen 80 default_server;
        listen [::]:80 default_server;
#       listen 443 default_server ssl;
        #listen 80;
        #listen [::]:80;

#       return 444;

        #ssl_ciphers aNULL;
        #ssl_certificate /etc/ssl/certs/ssl-cert-snakeoilnpem;
        #ssl_certificate_key /etc/ssl/private/ssl-cert-snakeoil.key;

        # SSL configuration
        #
        # listen 443 ssl default_server;
        # listen [::]:443 ssl default_server;
            # Note: You should disable gzip for SSL traffic.
        # See: https://bugs.debian.org/773332
        #
        # Read up on ssl_ciphers to ensure a secure configuration.
        # See: https://bugs.debian.org/765782
        #
        # Self signed certs generated by the ssl-cert package
        # Don't use them in a production server!
        #
        # include snippets/snakeoil.conf;

        root /var/www/html;

        # Add index.php to the list if you are using PHP
        index index.html index.htm index.nginx-debian.html;


        location / {
#               return 444;
                # First attempt to serve request as file, then
                # as directory, then fall back to displaying a 404.
                try_files $uri $uri/ =404;

        }

        # pass PHP scripts to FastCGI server
        #
        #location ~ \.php$ {
        #       include snippets/fastcgi-php.conf;
        #
        #       # With php-fpm (or other unix sockets):
        #       fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
        #       # With php-cgi (or other tcp sockets):
        #       fastcgi_pass 127.0.0.1:9000;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /\.ht {
        #       deny all;
        #}
}

You can see that I have tried a few different configurations and they all seem to not work properly. Initially, if I didn't do anything, it would just direct to the default new website NGINX page:

server {
        listen 80 default_server;
        listen [::]:80 default_server;
        # SSL configuration
        #
        # listen 443 ssl default_server;
        # listen [::]:443 ssl default_server;
        #
        # Note: You should disable gzip for SSL traffic.
        # See: https://bugs.debian.org/773332
        #
        # Read up on ssl_ciphers to ensure a secure configuration.
        # See: https://bugs.debian.org/765782
        #
        # Self signed certs generated by the ssl-cert package
        # Don't use them in a production server!
        #
        # include snippets/snakeoil.conf;

        root /var/www/html;

        # Add index.php to the list if you are using PHP
        index index.html index.htm index.nginx-debian.html;

        server_name _;

        location / {
                # First attempt to serve request as file, then
                # as directory, then fall back to displaying a 404.
                try_files $uri $uri/ =404;
        }

        # pass PHP scripts to FastCGI server
        #
        #location ~ \.php$ {
        #       include snippets/fastcgi-php.conf;
        #
        #       # With php-fpm (or other unix sockets):
        #       fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
        #       # With php-cgi (or other tcp sockets):
        #       fastcgi_pass 127.0.0.1:9000;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /\.ht {
        #       deny all;
        #}
}

As a final note, and not sure if this matters, but "default" is not symlinked in /etc/nginx/sites-enabled...

So what am I doing wrong?

Using Nginx to Block Connections that aren't addressed to my domain has my earlier answer on this topic.

So yes, you need to have a server block with default_server directive. And the file that includes the server block needs to be linked to sites-enabled, otherwise nginx does not see the configuration.

You should use nginx -T to see what is the configuration nginx uses.