I'm not sure usability is moving in the right direction with KDE. Over the past years, more and more applications started to hide menus by default, sometimes adding hamburger menus instead.

There is also a "new way" (I believe QtQuick-based) for applications to create popups, which results in them not being separate windows anymore. System Settings makes prominent use of them for example and those popups just behave entirely different than one is used to. As far as I know it's not even possible to navigate these popups with the keyboard.