Major problem in league's community

There's a massive growing problem in league's community. specially in ranked games for lowers ranks. (from sliver and down). I would like to have a discussing with you on my past experiences. Many people would agree on this that league of legends is a massive salt. From trolls to down right disgusting toxic people. I'm really thrown off to why they aren't getting banned. Not only that but they hold other people back by afking and trolling. It's really not fair. I just had a game where our sup decided to give up because the jg was making a few mistakes and that he died. he just afk and decides not to help. Riot i dont know what you do to banned or suspend people, but those type of people are worth of being suspended. Keep in mind I dont generally care if your bad at the game but if you gonna try a new champ or new lane that your not familiar with. Forgive me if Im worng but do yourself and other people a favour not try in ranked, because other people are trying really hard to climb and you just pulling them back. If your bad at the game i understand that but just because ur doing bad doesnt give you the right to troll, afk or being toxic. This goes out to everyone, I dont mind if your bad at the game, have the good mind set of trying best to win and work as a team and listen. Take other people opinions if necessary, either about your build or your play style because thats how you win the game. If you are so high in your ego, you will never win.

PLEASE RIOT investigate more on this matter, and also pls explain to me the process of what the needs for a player to be suspended or banned. This board is not hate against riot or anyone, just want to put more awareness on this growing problem.