Attempt #2 - original post removed - I'll change it a bit in a hope that it doesn't have the same fate. FYI - I'm not and was never asking for personal help - I'm advocating for an urgent overhaul of the player punishment system.
Cyber bullying is not ok, it's illegal in Australia and should not be tolerated at all. I know Riot will tell that they don't tolerate it, but when you consider that I never get a notification that someone has been banned because of bullying after I've reported them, it seems like they passively support it (a bit harsh I know, but that's how it feels sometimes). Now, I know the counter to this, it's only the last report that get's the notification, but for bullying, it should only take one report, no more. Zero tolerance!
Yes, I mute them when they bully me, but by then it's too late. Unless you mute all when the game begins, which would be a shame as I've had many great convo's during game, it's not a prevention tool, just stop more damage.
ZERO TOLERANCE is the only option. Fix it now. stop banning people for retaliating, give them chat bans if you have to punish them, punish the instigators. They all think it's ok to bully someone, just don't get angry back coz then you're the bad guy. Your policy on bans and not doing perma chat bans simply isn't working. One definition of insanity is doing the same thing over and over and expect to get a different result, well, currently Riot is insane. It's not working and it never will work. The way you deal with toxic behaviour needs a drastic overhaul and it needs to happen fast!