I can find billions of comments on this board sub-section of people either saying that they hope someone gets banned or that they are glad someone was banned or cheeky comments like "you'll be banned soon" or "enjoy your ban".
Riot games and players on here are under the impression that their role is that of a counselor whose purpose is to correct your toxic behavior.
So, are you just going to lump a handful of jerks in with the people you just said felt that their role was that of a counselor? Because, you'll find that those are two very distinct groups, and if you're going to make an argument about one's behavior (in this case, your argument that Riot and PB regulars only want to see people get banned), you should be referring to the real group of your concern (the jerks, not Rioters/PB regulars).
Instead, you're taking one groups' actions and pointing at another group entirely as though they're both one and the same.
This isn't a rehabilitation center...
No one said it is.
if players are being toxic but no one else is affected by it, are they really even toxic?
This argument hinges on nobody being affected by toxicity - which, by the way, people do. Before you say that they don't, just note that a good handful of people who use the whole "I was just defending myself" argument were very clearly affected by toxicity - that's the whole reason they often say they retaliate, after all.
(besides, that argument doesn't make sense - "if they're toxic but no one is affected, are they really toxic"? the answer is yes, the fact that they're defined as toxic, regardless of whether or not they affect others, means that they are toxic.)
There really is no logical justification for an inability to self-mute at this point other than teaching players proper online etiquette.
Maybe, but I'm seeing no logical justification for such a feature, either. Besides, quite a few people could use a refresher on online etiquette, as it were.
Why the hell should an online video game company be doing this in the first place?
I dunno, because their rules tie in particularly closely to said online etiquette, and it should be expected of everyone to be able to, at minimum, have that level of etiquette?
Again - you keep asking on one side of it, but don't propose anything for anyone on the other side to consider.
This is a video game, not a social media / networking website.
Aaaaaand that means people should have to deal with toxic assholes flaming and bashing players left and right......How?