I found the best comment in the world on a youtube video on what Riot needs to do.

"To drop my few cents on the topic, I disagree with Riot's punishment-philosophy. The way I personally think it should be, would split punishments into two categories regarding Gameplay and the Chat. A chat-related offense should receive a chat-related punishment such as restricting the player from using the all-chat and limiting the amount of messages he can send. But it should not be answered with limited or permanent account-bans, as players have various ways to handle rude messages or spam, such as muting the player sending them or turning off the all-chat or the chat-window as a whole. Gameplay-related offenses, such as intentional feeding or inappropriate amounts of AFKing should be answered with gameplay-restricting punishments such as locking the player out of ranked matchmaking or matchmaking in total for a limited or unlimited time. I believe that this is the way it should get handled because dealing with rude, or using the buzzword 'toxic', players is already a really easy task and I cannot agree with the idea that such behaviour should lock you out of playing the game at any time. I do not intend to encourage uncivil behaviour in the ingame-chat but I personally regard 'flamers' or 'spammers' as way better teammates to have than AFKs or trolls. Yes, they will drag themselves and the team down by making rude comments and unnecessary trashtalk, but an intentional feeder straight up loses your game and potentially even that very important promo you were taking so seriously. I think that Riot needs to neglect some of their efforts to 'reduce 'toxic' behaviour' since the option to mute someone ingame is already granted at any time. This makes players that demand additional focus on preventing rude behaviour, honestly, seem like crybabies and keyboardwarriors. Instead the company should focus on punishing leavers, trolls and intentional feeders. Especially in competitive matchmaking it is not so much rudeness but outright sabotage that should get you punished faster than the other."

To add my own two cents, any account that has been permanently banned for Toxic Behaviour such has flaming and shit talking should be unbanned and instantly put on a permanent chat restriction/ban.

TL;DR Take away peoples chat, if they start to int ban them, just because someone says something you don't like doesn't mean their account should be taken away. Give the toxic perma bans their accounts back but remove their ability to chat.