Are you ref to Internet social activity setting blocking? or CUT off 100% internet? for INSTAGRAM , facebook messanger, youtube blocking, it works in the way, that blocked device can still use any other internet service, but can NOT use INSTAGRAM , facebook messanger, youtube of the blocked acticitis.
When you block youtube, make sure block it before the device try to load youtube video, as it buffer first. or when you block it, the device will only start to load more youtube traffic after it finish use it’s local cache buffer.
34Kb is way too low. this need some research and try out , depends on which game and what internet service the device is using. but 34KB is way too low.