you see they have "queues" like this behind the scene (or at least can have), when they see that you are a new player they put you with other new player, when they see that you're playing at Eternus5 level a few games in a row they put you in a sweaty E5 games and so on. If you like to play in a chill way, they once again can figure it out and put you in more chill lobbies. My point is that it's not necessary to split queues to better match people. The only counterargument to this is that there are people who sometimes want to play sweaty E5 and sometimes want to completely chill on the same agent the next game, this is quite rare I think.