Are you using multiple screens and have something open on another screen that periodically rerenders? I have had a similar problem when having Ksysguard open on a second screen - every time the graphs rendered a new time step, my game lagged. Only happened on Wayland. My solution was to run the game inside of gamescope or to close the offending application.
Yes, you can either add external games inside steam and set their compatibility options to use some version of proton or use proton through lutris or manually.
Chrome […] is spyware. Don’t use chrome.
Oh it happens on Windows too, but wine adds some overhead, so you have less headroom on Linux. Same goes for DXVK / VKD3D - they add some CPU overhead.
Where are you getting these numbers? I have a 3080, used a 1080Ti before, and though my last direct comparison was a while (like a few years) ago, I had more like 3-5% difference in FPS in the games I tested, at most 10% in RS2 Vietnam, but this ultimately turned out to be a CPU bottleneck. I would assume (and, reading reviews on reddit, this seems confirmed) that the drivers have mostly gotten better since then.
When was the last time you used an Nvidia card under Linux? There are no performance issues compared to windows, haven’t been any in YEARS.
If by that you mean ray tracing, no. Nouveau can’t and won’t ever, NVK might but it will take time.
As someone who has been using Nvidia and Linux nearly exclusively for many years, I am interested in the aspects you think their drivers suck in. I have had literally no problems with them in the past 2 years, performance is incredible, Wayland just works, …
Just not true anymore. Must have been years ago that you used Nvidia on Linux. As someone who has been using Nvidia GPUs under Linux (Manjaro KDE mostly), recently also under Wayland (since plasma 6), I can attest that the experience is very good, no “tons of small issues”.
Still though, since OP wants no proprietary drivers, he has to go for AMD, since nouveau is dog shit.
I am running Manjaro KDE on two general purpose PCs, both with Nvidia graphics, both without problems.
On my living room gaming setup (also Nvidia), I am running Bazzite, which also runs very nicely.