Why do you give intentional feeders a slap on the wrist?

My last game, someone got autofilled into support in a ranked game and goes "Top or feed". Top is my rightful role and I refused. Once I entered the game, he declares that he will intentionally feed if he does not get Top, he said this IN chat. He then proceeds to intentionally feed all lanes and the enemy jungle attempts to defend him to troll and say "Oh he's just lagging".

The game ended in defeat and I reported him along with the enemy jungle. What happens?

Absolutely nothing. He is currently playing a game as we speak with no consequence.

And he even admitted in the chat that he has been doing this for four years.

Why are you so loose on intentional feeding in comparison to someone dropping the F bomb? This makes zero sense. He should be banned from Ranked temporarily until he learns to play courteously, which clearly, he has not.

I can also provide the file for replay if that's possible for access and capable of being shared. I want this player punished to the fullest extent possible.