Earlier quoted context omitted.
Exactly. In addition to the functional problems you outlined, every Linux GUI I've tried feels fake and plasticky, like it was designed for kids. Gnome is miles ahead of where it used to be, but design-wise it is now at about Windows 98-level. Is there a problem attracting quality graphic designers to open source projects?
I think it requires a change of mindset. I've been using Linux exclusively on all of my machines since 2004. I started with KDE and then switched to Gnome 2 and finally Gnome 3. Everything looks clean and normal to me. On the other hand, every time that I need to use Windows (even Windows 10) it feels strange. So I guess it's a matter of perspective.
In my opinion, there is no reason the design can't be made to look better while still maintaining the familiarity (like OS X mavericks did, for better or worse).