I don't see why you switched to Android then in the first place, because only iCloud uploads will be scanned on iOS. Also I can't think of a single manufacturer with better privacy practices than Apple except for custom ROMs.
For now… I think it’s easy to imagine what v5 of this tech can do, what additional databases come into scope
over time. The potential of abuse by governments, and the principle of on device scanning. Cloud scanning doesn’t bother me as much… but this feels like a step
too far. Some things are reasonable, this doesn’t seem so.