Because there is a block player option to stop text harassment and a report player conduct. If someone just wants to leave matches because they didn't get a god hand to win then there is no options for that. The only people against this want no accountability for their actions because they just want to be able to instantly leave and join other games. It works for every other game system with early leaver penalty, here it would be no different and stop players from leaving unless they can convince 2/3 of the lobby to forgive them. I'd liken this to pve players complaining they get killed in a pvp game when there are slews of pve games for them to play but they join that game regardless....this is essentially your take. You'd join a early leaver penalty lobby and get mad when you get hit with a penalty because you leave, despite it being an option to not join that lobby.
So no it wouldnt be players "doling out punishment" as its hardcoded in the game lobby you join. Do you join a matchmaking system for other games with this same system and complain its the players giving out punishment as well? I think its completely asinine and selfish you don't want to be held to a punishment system you willingly decided to join. I am blocking you now because I don't agree with your opinon and you seem to be willfully misconstuing points I made and I consider it toxic.
@Firedrake early leaver would be at any point in the game. Don't want to have to abide by those rules? Don't join the lobby, nice and simple. If you do and have a valid reason to convince the other players then they can choose to vote forgive the penalty for you. Once again its people that don't want accountability that are against this option. The laughable part is they don't have to partake but still against it which means those players intentionally join and leave games early to abuse the system we currently have.