The DE is very important to me, and for me that is KDE. Tbh I find Gnome horrendous to use - too locked down, too uncompromising in it's design. If you like the paradigm then I imagine it's decent - certainly looks very slick. KDE on the other hand is very flexible and has been easy to tune it to exactly what I want.

But i'd say switching DE shouldn't be a "barrier". Almost all distros support multiple DEs, and Gnome or KDE is a common choice.

When is comes to VR, you can set up an alternate X11 session which only runs Steam in gamescope mode, with minimal or no desktop environment. /usr/share/xsessions/ contains defined X11 sessions; you can manually add one that literally only launches one program via a .desktop file pointing to a script (e.g. launches steam in gamescope mode with a specified resolution). Or you can install a very minimal DE such as OpenBox or i3 and set that up to autolaunch Steam in a window or big picture/gamescope mode. This way whenever you want to VR, you log out of your Gnome desktop session and then login to your "Steam" session, and almost all resources are available for Steam and games with minimal overhead. The minimal DE route is probably the better route just because of options to get out of crashes and problem solve. Either way, this route bypasses the Gnome / and general Wayland issues with VR.