So when you break blocks in 1.15.1 its give you a little bit of "lag" making your cam going to the previous blocks, like a millisecond, and its very annoying if you have to collet a lot of resources, the video is in a Realm, but also happened in survival singleplayer , first i thought it was just me but i asked a bunch of peoples and they noticed the same, in those people that i asked was the youtuber RaysWorks