> none of them are automatically fixed with skeuomorphism

True.

But they absolutely need to stop hiding functionality in order to present a "clean" interface.

Sure, I've seen some cluttered interfaces. I recently launched LibreOffice Calc and damn there were a lot of buttons on that toolbar (I may be using an insanely old version).

But like...disappearing scrollbars makes zero sense and should never have been implemented on any interface.