Community acceptance of toxic behavior

So with this whole thing about dunkey getting banned I'm seeing a lot of people mad at Riot about banning dunkey, and in general people defending/ being more accepting of the toxic behavior. Some of the common responses I'm seeing on reddit and on the boards is if a person is toxic you should just mute them. Or people should just get over it and if they can't they shouldn't be playing the game.

One comment in particular just was outright disgusting to me the person said "I still don't understand why wishing cancer is the worst thing ever in this game. It genuinely makes me giggle when someone types that. If you take offense from someone else's wishes you probably have an issue yourself imo"

For me personally it's a huge deal, I have a friend who used to have cancer (cured now), when I first started to play league it was with her. So about a month in we are still learning the game and we get into a normal game and she isn't doing so great (who doesn't have a bad game at times, especially when your fairly new to the game) and someone on our team says they wish she gets cancer and dies. My friend just starts to cry, it was a horrible experience for her and me. I don't understand how someone can say that to another human being, and how people can defend someone like that. My friend can't unsee that so no that mute button isn't gonna help to everyone saying just mute them.

You play a game to get away from life, to relax, to have a good time with friends not to have people tell you to kill yourself or that they hope you get cancer and die. Do people not realize how serious and offensive behavior like that is? If you've known someone with cancer, or has committed suicide don't you realize it's not something you should be joking about much less wishing upon people? As a community we shouldn't be defending or ignoring behavior like this, it's utterly disgusting when people blatantly defend it. I realize it's not everyone defending toxic behavior but it's still a decent amount of people.