I am having the same problem on my switch 1.20. except I was in a creative world to begin with. Doing what you did, using the rain command and then the clear command finally cleared it. I have not had the problem on my survival realm world. Ridiculous this isn't resolved 3 years later.
It is 2-14-23 and I'm still experiencing this. I've seen it on my switch also, but the switch has a ton of other issues making Minecraft un-playable on the console. Mobile is better. The only way around this is putting every animal inside a fenced in area without a lead. Leads are useless on Android mobile.
I have epilepsy and could feel a seizure about to occur after using a night vision potion tonight. Did your experts try this in a small dark room on a small screen like a switch? Doubtful. I cannot use potions because I don't want a seizure. At least having the option to toggle particles off on bedrock without commands would be nice. But at least we get a new virtue signalling yellow text message daily. I don't know what I'd do without those.