Overall we're pretty minimal when it comes to animations in product (i.e. here's a quick 22s recording of navigating between screens/opening properties panels in product today: https://video.non.io/video-2940009905.mp4) as we really want to convey that the app is snappy/performant. Definitely keen on diving in if you're experiencing otherwise. Happy to chat here or my email is jake@figma.com.
Regarding platform specific performance - it shouldn't affect things as long as you have GPU acceleration enabled. The majority of us over here at Figma are using OSX FWIW.
Dragging any object is laggy--particularly so over the slightly pinkish/purplish background area.