

I just saw this reply now and wanted to tell you a bit of my experience as it doesn’t sound too far off from my own!
I think that move will work out nicely. I’ve been on a 5800X3D + 6800XT for a while now and completely switched to Linux for pretty much all gaming and desktop use 18 months ago. My experience with arch based distros running KDE Plasma has been virtually flawless.
I decided now before the new AMD cards are coming out to get my hands on a RTX 4080 Super just to see how far Nvidia on Linux has come before I make a decision in March on what vendor to go with.
I can confidently say both Nvidia and AMD run my setup (1x 2160p @ 120hz, 1x 2160p @ 240hz, 1x 1440p @ 120hz) in KDE Plasma without any problems at all in desktop use. But modern DirectX12 games will perform slightly better on AMD for the time being until Nvidia does something about their drivers on Linux.
So no matter what direction you are looking in the future I think right now is a super good time to make the switch to Linux!
Also running my 9070XT Red Devil on Linux with the exact same OS setup as you. Some games have performance within 10% of Windows. Like Space Marine 2 at 4K. However since the drivers aren’t quite on par with Windows yet since it just launched. Some games perform a lot worse.
Monster Hunter Rise cannot draw more than 140-180W so performance is about 40-50% less than on Windows. The same power draw problem affects Space Marine 2 where on Windows it easily runs at 110+ fps at 1440p but Linux barely goes over 75 fps. Wattage never goes above 230W.
I am hopeful the power draw problem will be fixed in the future and the drivers getting a bit better in 6.15 and future mesa releases. A really strong launch showing on Linux for sure!