If you're looking for a safe space, competition isn't for you.
Whether or not people get punished for it, the harsh reality is that a team-based competitive game where your allies are almost always strangers and their actions are very capable of undoing good performance from yourself will always harbor feelings of anger and frustration towards teammates who fuck up.
Continuously dragging on and on about how someone was a meanie to you because you somehow went 0-13-0 unintentionally is just ridiculous. If you can't handle the kind of environment created by this type of game, this type of game isn't for you. If you don't want to deal with the reality, go play a different game. Because no number of punishments dealt is going to change the nature of this one. There are plenty of free to play Player vs. AI games where anyone you play with is working towards the same goal; there's no reason for you to be playing a game where half the people you play with are trying to beat you.
Club Penguin Island was released last year, if you can't handle a rated T game.
Edit: Someone in the comments hit the nail right on the head. I'm not encouraging flaming. Of course not. Usually that only tilts your teammates. But, "if you can't take the heat, get out of the kitchen." While the main body of this post is me saying that picking a different game is a solution, muting everyone is also a way to guarantee you'll never encounter any heat.
in a game is competitive trash talking and bullshitting. This is acceptable in a safe space.