Ehhhh I disagree that package managers handle cleanup correctly, I’ve certainly had tons of dotfiles left in ~/ mucking things up when reinstalling apps, even those that have been purged by package managers.

The package manager, much like the windows installer/uninstaller, relies on the developer to be responsible in declaring how the package is meant to be managed. If users have manual steps at installation, they will have manual steps at uninstallation as well.