Game data and video data have very different constraints. Depends on the nature of the game, of course, but with jitter and all that, video can just run a buffer and manage network conditions (more) trivially, but a game needs things to be a lot tighter to avoid gameplay-impacting desync

It's true plus you cannot just send a snapshot of 100 kilobytes or so from server to client with 1500 byte MTU with regular IPv4 packet fragmentation and reassembly due to packet loss amplification effects.