My SE also has this problem after updated to watchOS 11 RC. I reset my watch, but it didn't work.

I have this problem too, and my mouse often freezes and can’t move normally.......

I also have some problem with my bluetooth on my Macbook air 2020 M1. My mouse moves very slow. Firstly , I think my mouse was died, so , I bought a new apple magic mouse , but this problem is still there. I finally find a way to fix this, just turn off my wifi, then the bluetooth mouse will work well again. I do not have this problem before yeaterday, I do not know what's wrong with my Mac. I think this might be relate to WiFi and Bluetooth interfere, but I don't know why this suddenly happened yesterday.