One way to get rid of toxicity
We all know it, we all hate it. So, why not deal with it harshly?
My idea is this:
When someone says a phrase like "kys" they get a debuff. Something like 30% slow for 5 min. Or 30% less dmg. If they do it again they get another debuff and so on. If they get to the point where stats are 99% gone then they get a ban when game is over. That way they know right away that they're being toxic and they either choose to not do it, or they choose to be banned.