I think it's interesting Riot tries to foster a healthy community considering their design.
You enter champ select, and some guy starts raging and gets abusive, or perhaps decides to break the meta in ranked and takes a champ who doesn't belong in the jungle in to the jungle.
Can we report him? No, you have to actually play through an entire game with this person to have that option. Can we dodge? Not unless you want a drop in rank, and an automatic loss in your series.
So, you decide to stick it out and mute him in game. Too bad the muting doesn't stop the nonstop pings he drops on you every 30 seconds.
The game starts. You have /allchat turned off because you've had a bad day with enemies raging at you in it. But, it doesn't matter that you've muted the entire enemy team, because when you go to lane, and make a few good plays, but miss a kill on your lane opponent, he then stands there smashing his /t and /l and /d macros. Or, worse, he kills you and drops that badge signal showing you his mad skillz rank 4 champ rating.
I feel punished when I play League.
It's not just the occasional rude player that makes this environment toxic, but the very system we play in.