Configuration installer is an installation profile, not a module. It's like one of the standard installation profiles that comes with Drupal core, such as Standard or Minimal.
Once the site is installed using an installation profile, you cannot change the used installation profile anymore; it's not like a module that can be uninstalled and replaced with a different module. That's why an installation profile doesn't implement hook_uninstall()
.
The only way to use a different installation profile for a site is reinstalling Drupal and choose the default installation profile (Standard).
Manually changing the installation profile would require to change any reference to the old installation profile in the database with the reference to the new installation profile, execute the new profile hook_install()
implementation, and eventually reverse the changes done from the old profile hook_install()
implementation.
There is still the configuration added with the configuration files in the config/install and config/optional directories for the installation profiles. (See for example, config/install and config/optional for the Standard profile.) The configuration from the old profile should be removed, and the one from the new profile added.