I just got banned for 1 hour due to a game lagging me out to home screen. So me getting thrown out of a game enforced punishment as if i quit the match!! Thanks for that update 
Redirecting queries about matchmaking bans to the official ban thread, please read over the first post before responding:
https://www.halowaypoint.com/en-us/forums/84ad72a8b51847978545f685f651fc15/topics/the-official-halo-mcc-why-was-i-banned-thread/95de2d50-5e10-42db-9490-c24efbd2dc74/posts