The latest Hotfix 24 should address the issue with performance. If after updating to Hotfix 24 (version number 4.1.1.5009956) you are still experiencing the same performance issues, please let our Support Team know: https://larian.com/support/faqs/how-to-submit-a-bug-report_85
Still unplayable on Macbook M1 Pro (32 Gb RAM) with MacOS Sequoia. FPS shows above 20-30, but I have video and sound stuttering almost from the very beginning after loading my saved game (Act 1). Windowed mode/Dynamic Crowd Off/Medium settings don't help.
Since this thread is almost a year old with several patches and fixes in between, it's hard to tell if this is the same bug. This specific issue is also reported fixed, so please make sure to notify Larian Support that you're still having trouble.