Its not easy but i tried
Whatever i guess its better to just think about the problem: What is supposed to do a system that ban people like this ?
First question would be, on what can a system like this really work... Easy data you can gather are chat logs and game stats...
Problem is you cannot really use game stats, like the number of death, the picks... To really determine if someone is bannable...
Like, feeding or trollpick isn't a bad behaviour... Maybe you just don't play good today. Maybe you bored and want to play another champion.
Only intentional feeding is bannable. But its not easy to understand if someone is intentional feeding from the data of the game.
You can ban people on keywords. But here again the problem is to evaluate in which context it has been said.
When you have a community you can simple ban insults because you know that you do not want to see those words in ANY context
But imagine if someone say: "you are a @#$!", and you answer "why do you call me a @#$! ?"
A perfect system would have to understand that the second sentence is a question and not an affirmation...
Another exemple: the word "retarded". It can be an insult, but it can be a way to say that something is extraordinaly like "omg its so retarded !"
So if u understand that unless they got the best AI in the world, they have a simpler system...
A system that will count the number of bad words, the number of reports, try to value if the one sending a report is toxic too or is suppoed to be a good guy... And try to correlate those data...
So it will be very hard for them to understand the meaning of the grammar in context.
They will implement things like: If the message is just "retards" then its an insult, but if there is another word in the sentence then it is potentially NOT an insult. That is why saying "kys" is insta ban but saying "i think you should probably kill yourself" is not insta ban
In this exemple if i say:
"i think"
"the ennemy team"
"is"
"retarded"
i will count as extremely toxic, while i would simple be not polite as slightly stupid but not really "bannable"
And about some the report system...
So what this system do is basically the same as the downvote system... See my post are downvoted because i "seem" arrogant.
So with a system like this i would get banned because people don't like my point of view
This is more or less what finally happens with a report system like this ^^
All those problem are simply extremely difficult to solve !
Another exemple:
In ranked so many people flame...
But you get reported usually when game is lost. It means if you carry all game you get less reported ! Even if you are a flamer...
Another exemple: They all flamed but one get punished... That person will obviously think its normal he gets punished !
And yes it is... But other don't get punished and also think its normal they didn't get punished. (its called bias)
also i found an article that is maybe able to bring some insight " https://en.wikipedia.org/wiki/Philosophy_of_artificial_intelligence " i didn't read it though...