Riot just perma ban them

So I'm a relatively new player trying to get to silver 4, currently bronze 1. I see why people call it an elo hell. The amount of trolls that just go into your game to make sure you lose lp is absolutely crazy. Just last game we have an adc that locks in anivia. None of us can dodge because we were all in promos. This same anivia proceeds to then feed multiple lanes and then leave the game at 11 minutes. Riot simply would give them a 5min leaverbuster. I say just take their account and just totally ban them from ranked mode. I'm trying to climb seriously. If there are players that queue into rank mode just to troll just ban them. Make ranked a place for people who want to progress and improve their gameplay. Not a place where melons can come in and troll just make sure you want be seeing that next rank anytime soon.