I still have to keep Windows around for (ironically) performance reasons.
Some sim games like Rimworld and Stellaris just have a big hit on linux for me, native or Proton. And in a sim game, that means slow turns and stutters you can’t avoid instead of slightly lesser graphics. And it’s not sublte, native stellaris is like a good 30%-40% slower with even higher spikes last time I benched them back to back.
I do find the steam deck is kind of buggy, at least for my use cases (usually docked, mostly used for emulation, and so on). But I’m thrilled that it exists, so I’m trying to support it as much as possible.