It looks like Valve has mostly solved it (at least on Linux) with Steamplay by not using Windows' DX12 API.

I haven't played on Windows, but it runs great after the shader pre-cache update.

I was worried about the same thing but happy to report that it's been pretty stable for me. The only stutters I've seen have been straight after alt+tabbing back into the game. I've had one crash in about 50 hours.

I'm running Win10 on an i5-12600kf and 2080 super.

There is a shader cache issue present on Windows that seems to be completely fixed by the latest Proton version on Linux.

No stutter or fps hitches for me in Manjaro with a Vega 56