Merging is still in the game. The only way to counter people merging from higher levels to lower ones is to merge a game yourself and BOOT that higher level person. If they remove booting from the game what's stopping me from getting my level 56 down dozens of levels to farm for kills? What are people going to do? They can host a new game. But if my game (the one with a 56) has only one person in it and their game doesn't have a full lobby, then it would merge into mine as soon as their game is over and be an endless cycle.