I guess the "solution" is to run parallels and windows on older Mac systems.
I have the same iMac, and the Windows version of BG3 is completely broken in BootCamp — crazy stutter, frames drop down to 5fps and then go back up, all the time. It feels like a major driver issue. Native Mac app is the only way to run it.
I hope they fix the macOS version. Raw performance isn’t actually worse, it just got a lot of traversal hiccups after the patch. And Fullscreen doesn’t work correctly.
