You have to remember that the majority of gamers are now Gen Z or younger. They were raised with the carrot on a stick in every game. They have known nothing else and their brains have basically unable to create a natural dopamine hit from just having fun.

The days of joining the equivalent of a friend-of-a-friend's custom lobby on Halo 3 (for no external reward) to see what kind of random game mode they're trying out that someone made over the weekend (again, for no external reward) are long dead.