AMD is ideal but Nvidia is fine. Basically any game that would work on AMD will work on Nvidia (only exception I know of is the VR mode of Phasmophobia edit: apparently this was fixed ~1yr ago). Gamepass still won’t work though - blame Microsoft for that one.
That said, Nvidia has more of a performance hit when switching. Ancient Gameplays recently did a video comparing Nobara vs Windows 11, with both the RX 7900XTX and the RTX 4080 Super. These were his average results across 20 games:
RX 7900XTX: 1080p +2%, 1440p +0%, 4k -2.2%
RTX 4080S: 1080p -13.8%, 1440p -13%, 4k -10.2%
So your games will work. They just might run 10%-15% slower until you can snag an AMD card. If you’re interested in fully committing, looks like most used 3080s are going for ~$500 on ebay, so you could probably get an AMD card and get most of your money back.
Is that true? It looks like at least some people have gotten AMD GPU passthrough to work unless I am misunderstanding.
Also, as an FYI most VR games worked well for me on baremetal linux through proton. Half Life Alyx, Beat Saber, The Lab, COMPOUND, Walkabout Minigolf, and 2-3 more indie titles all worked. Although I guess you need to have the right headset - I think only the Valve Index and a few HTC headsets work with minimal effort on linux, others might work with a lot of tinkering.