I am familiar with KDE and years ago when I was in the community I know that most of the apps are just a few unpaid volunteers/developers, in their free time add missing features and fix bugs. There was no big ego designer that had to approve if we add a new menu or feature or any study to decide if a new feature might segfault the brain of some user. Each maintainer decides if a feature makes sense and the design was usually the generic Qt/KDE layouts , no freacking custom widgets that a user can't theme.

I would be interested to hear if there is a major difference between GTK apps that are not part of GNOME and GNOME first apps .