I'm on the latest HyperOS for my Xiaomi Mi 10 Ultra (CAS) and it's exhibiting the same problems that I used to have years ago on the official Chinese MIUI ROMs.
Namely, 1) accessibility apps just quit working randomly and 2) notifications stop working (I get zero notifications from Google Home for instance for things my cameras detect).
I've set all these apps to have no battery restrictions, they are set to auto-start, and their notifications are turned on and not blocked.
This is on a near-fresh install of HyperOS as of a few days ago after a full system wipe. Previously I was on MIUI which had none of these issues.
Anything else I can check to fix these things?