Source is this video:
Windows Was The Problem All Along - Dave2D
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 could barely get Minecraft to run 20fps on this old laptop I had given to me a few years ago. Loaded Ubuntu on it and Minecraft ran near 60fps. Blew my mind.
Pull the DE out and you could probably squeeze that performance out on a modded instance