MCC never had it and it was better off for it.
Not sure why it’s needed for the bot games, but there’s enough quitters and fools in matchmaking to make it necessary.
What’s bad about JIP?
I personally like JIP. Now I don’t have to get demolished 2v4 all the time like in halo 5. I don’t believe it is in ranked though.
You usually end up joining a losing game. And when loading takes super long, it would be really annoying to join a match that’s half over.