We could obviously compare performance between windows and steamOS before on the steam deck, or between windows and Bazzite on other handhelds. But this is the first time we have had official windows and SteamOS builds for the same hardware.
I was kinda joking, but the game still stutters and has fps drops regardless of the hardware it's run on. Digital Foundry has a pretty scathing performance review of it.
It's certainly playable on good hardware (assuming you aren't super bothered by dips), but it also performs way worse than it should at any hardware level.
I don't consider the game a good performance benchmark for any piece of hardware because it's performance is abnormally bad, and there's no hardware where it can run without issues.
So for real though, while it's disappointing and I am nowhere near the 500+ hours i have put in previous titles, the hardware is not going to do it. The game eats VRAM like my brother's ex ate cake.
But, I get about 5 fps @2k and 9FPS@1080p better on my Ubuntu image than my Windows 10 image.
Ryzen 9 5900x
Radeon RX 7900 XTX 24GB
32GB DDR4,
both images are on different 1TB nvme drives