Jumping off the map might be bannable sometimes but beyond that this playerbase has shown they will try to manipulate just about anything else that would seem to make sense. Even with map jumping some people will convince themselves they're doing it altruistically to save their teammates. And that's just something that will lead to more bad matchmaking. But yes if people are jumping off the map they shouldn't really ever get matched with those playing the game right or in lobbies where the game is working the best. Everyone needs to be real about how that causes some people to act as a whole when they feel they're being pumeeshed though. Unfortunately something that makes matches is really supposed to be this thing were the people that do the most of what they're supposed to kind of automatically move up without the feeling that other people have to be in there making sure there's bouncers for map jumpers.