Comment 2 for bug 1852028

The path variables alone don't really tell KiCad where your libraries live. KiCad does not search some (configurated) path for libraries.

The path variables are there to make library tables portable. The library tables that are distributed with KiCad do use path variables. Meaning the default installation does indirectly use these path variables.

Be aware that the library tables are not updated by the installers (they are user files, the installer is not allowed to touch them). Meaning if you have trouble with "wrongly" installed libs then you most likely have an outdated library table. (The installer can not do anything about that -> This requires user action! It would be nice if there is an easy "reset to defaults" option but right now the only way to do this is by deleting your personal lib tables.)