I have the same rig as you minus watercooling, and I assume you have AMD Ryzen 7 9800X3D? Anyway, it's my only PC now, I game, dev, run local models, edit photos, edit videos, all in Manjaro. I get ~70FPS in Cyberpunk at 4k, every setting at "Insane" or whatever goofy thing they call it, Ray tracing on path tracing off, with no framegen but with DLSS set to quality. Without DLSS I get around 40fps. Seems equivalent to what I see online with people with a similar build on Windows.

I run hyprland, seems to be the only wayland based keyboard-forward WM that has good nvidia support (and, allegedly, supports HDR, though I haven't got this working). I heard gnome was pretty good otherwise. I was running i3 before and it also worked fine, however once I got into wanting to get streaming working, there wasn't good compatibility between i3/xorg and tools like sunshine. I believe steam streaming worked fine on it though iirc.

The only thing I miss from windows: easy streaming with sunshine/moonlight. Steam streaming works (usually heh) but it took me a couple days of fiddling to get a stream to work at all through sunshine, and it is choppy. But for local gaming, I don't miss windows at all, I'm so glad to finally have all my drives converted from NTFS to ext4.