I'm unsure if this is a bug or not, however it is rather annoying—when sprinting on the latest bedrock beta (Ver. 1.16.0.61) the FOV doesn't seem to zoom like its intended—its just on default, it doesn't move at all. Additionally when sprinting, there seems to be some sort of 'delay'... making the player slow down for a bit and then resume to sprinting (I've noticed a high probability of this occurring if the player is attacking a mob, and sprinting at the same time)–the delay is very similar to a server lag; I'm uncertain if this is recreatble however, it just occurs. But yea, thanks, I really hope you have the ability to fix this in a later update, thanks!
(Edit: After further analysis, I've come to a conclusion that this isn't a bug; I just mistakenly—and unknowly—turned off "Dynamic FOV", and as for the sprinting delay, I misinterpreted the acknowledgement of the "Berry Bush" and how it can cause the player to slow down—if not, damage the player.)
i have this issue too after updating to 1.16. its mostly cause by input lag making it unplayable. developer team need to address this problem ASAP