The "report this guy who hurt my feelings" syndrome has existed long before league.
I've been reported in runescape for telling someone their weapon was bad and for telling someone I didn't believe in god. I got reported for going to a group of people cheering for Zamorak and chanting Gunthix.
I've been petitioned in Eve Online for killing people in PvP (was fairly common)
I've had people report my Xbox live account for doing well in a match of Halo 3, or for telling someone their aim was bad and they shouldn't be using a sniper.
I've had endless instances of people raging and leaving starcraft games for any number of absolutely silly reasons.
My last decade of gaming is full of people seeking senseless vindication for how I've affected their personal feelings in some complethey irratonal way. It's not new in league. It's just people.
As far as "toxic every game". What do you mean. Angry and condescending? I am too. I don't think that's what riot targets most.
The people they punish are the ones who can't go 4 games without wishing cancer and aids upon 9 other people. The ones who aren't even raging at their teammates, they're just raging.These people don't belong in any online game. They belong in a therapists office.
Angrily trying to be constructive, which many entitled brats think is toxic, isn't really that toxic. It's often not helpful, but there's a difference between "if you fucking retards can avoid doing something completley mindleslsly stupid for 2 minutes, I can push thier inhib" (actual in game quote by me) and "u fucking noob shit I hope your mom gets cancer go uninstall you n@@@@r fuck you trash %%%got".
There are people who actually think the latter is an okay form of interacting with other humans. I don't want them in any game I play. I don't think it's as easy to get banned for the former.