Many reactive db systems are 'verbose' which means they would rather send two of the same update instead of zero. At least in my experience. If your code is written properly, this should not cause any issues. Gun is notorious for this. Firebase is a bit more predictable.
Just to offer an alternative explanation
this weekend my firebase project finally reached the point where I realize the need and utility of flux
I suppose my excuse is that it seems needlessly complicated and lots of guesswork to get right so I avoided it until now.