Argument for stronger punishment for verbal abuse

I had a revelation in my last game while playing jungle, the game started poorly with the enemy team invading our blue and stealing it. Obviously this is not the end of the world but our mid decided he was already going to start busting out the hate by shouting that it was my fault for being late to the buff and costing him his flash. He then dies very early to the enemy mid, and lo and behold the obscenities really start streaming now. I'll save you the details but you can see where this is going, as things go worse for him he gets angrier, causing him to lash out at his teammates for various reasons.

Now here is the dilemma; as he starts screaming for ganks I am forced to make a lose-lose choice, either mute him (which I did in this case) and ignore his already lost lane or attempt to save him by ganking a losing lane. Now for those of you that don't know the conventional knowledge as a jungler is to ignore losing lanes and help winning lanes snowball as its a safer play and generally leads to more wins. In this specific scenario with a feeding yasuo and a lee sin jungle on the other side camping mid I really don't want to opt into a gank in mid lane that will probably lead to two more deaths for my team. So the dilemma remains, gank for this guy who is screaming abuse and reward his negative behavior, or ignore him and pray to god he doesn't AFK (in this case I ignored him and he AFKed.) Either way this one player decided the whole outcome of the game as a loss for my side through his toxic verbal abuse. The fact that any other lane may be winning is irrelevant as a 4v5 is pretty darn hard to win, especially if before going AFK the person fed a good bit.

Side note, I'd be curious to know what the win odd are of a team that has a negative KDA player on their team that AFKS, compared to a team that had a postive KDA before AFKing (or one that never joined.)