It causes a bunch of weird controller errors, such as when a controller disconnects (or if the deck goes to sleep), it can’t reconnect again.
Just let it use the default version (which I believe should be Proton Hotfix, or whatever Valve decides it should be since BG3 is an AAA headliner, they’ll want this to work)
I fiddled with it a fair bit, and ultimately decided to just stick with the “Medium” default. With that, it’s pretty stable, with a few dips, but given the turn-based combat etc, it doesn’t really bother me.
(But that said, I’m an old-school PC gamer. I played DooM on an 8 MHz 386 at sub-10 FPS. I had to “lead” my shots to play. So my personal standards for game performance may be a little low.)