Toxic Behavior and it's Seemingly Random Punishments

So I somehow magically got the same person in two games in a row in High Silver elo. And managed to get nothing but verbally harassed by him for 40+ minutes in both games. If any reds read this It was the Braum and Janna games I know there's a policy about not naming names but for real..... I seriously cant fathom how someone can type that much (100+ all-chats in the second game). Long story short, I'm not the most positive player. But I've worked on it. A ton. I still am. Getting my jimmies rustled personally in ranked for over an hour? Not so fun. I know people who have gotten chat bans for considerably less.... and I know he got at least 2 reports in both games. I'm not even necessarily asking for almighty ban hammers, I'm certainly guilty of a rant. But how the hell does this system work? I can't imagine if this guy typed like that all game for two games that is not his regular behavior... I'm more looking for an explanation as to how people like that DON'T have at least chat bans.