I suspect KDE because most PC gamers are Windows users and KDE is closer to that while Gnome is closer to macOS (both in design and being restrictive).
For what it’s worth, when I moved from macOS to Linux I found that KDE Plasma customisation made it less frustrating to get the appearance and multitouch gestures closer to what I was missing on a Mac.
All of them, including Doom 64. I bought Doom (2016) on switch mostly for a laugh but it’s surprisingly playable. Never tried Doom Eternal though.