So there's 11.5 million active players per month, but autofill is still necessary?

Want the proof? https://www.riotgames.com/tags/player-numbers , and this was 3 fucking years ago, so the numbers are even higher than that. So tell me, why the is this shit system needed? All it does it reduce queue times by 3-5 minutes, piss people off, forces players to play roles they don't know how to play, and ruins ranked experience as a whole. It's just a tilt factor, nothing less. People act like watching Youtube while the queue is going isn't a fucking possibility, or the fact that you can, oh I don't know, PLAY SOMETHING ELSE WHILE YOU'RE WAITING? Spoiled fucking brats, people can't wait 6-8 minutes without having a damn tantrum. But in all honesty, answer the question. Why is this system needed when there are well over 12 million active players a month.