Defending yourself is a basic human right.
There's defending yourself, and there's getting into petty flamewars that serves no purpose. There's a pretty substantial difference between self-defense and starting into a shouting match, and in League, it's always shouting matches in the case of "self defense".
Defending yourself would be preventing further harm; in real life, that can involve retaliatory attacks where necessary (self preservation typically comes before the well-being of the attacker, though even that has its limits), but in League of Legends, defending yourself is muting the person who's flaming you. That's it; it is the singular most effective way to prevent further harm.
Y'know what doesn't prevent further harm? Flaming back. Getting into a flame war just exacerbates the issue, and no matter which way you spin it, be it "defending yourself" or "standing up for yourself" or what have you, you're not preventing further harm, you're just making the situation worse.
Even if the ToS states that any "negative" behavior means that automated bans and restrictions are final, it doesn't mean that it is right. I believe that there is a fundamental issue with Riot's stance on player behavior.
And if you don't believe that the rules are right, then you are free to find another game whose rules better suit you. The majority of League players do not want counterflamers, and, ultimately, Riot doesn't either - and what they say goes.
In my honest opinion, players who talk back to a toxic individual in self defense should go unpunished. Its not hard to track who typed first. And in cases where it isn't possible for the automated system to track this, a manual review would be necessary.
And you're entitled to that opinion, but that doesn't reflect the opinion of the community at large, or Riot. Fun fact; back when the Tribunal was a thing, where the community was allowed to vote to pardon or punish players for chat misbehavior, the vast majority of cases where people defended themselves counterflamed were voted to punish, because people do not care who started it - both flamers ruin the game for everyone.
Punishments are too severe for Riot to refuse to go back on them.
Uhhuh. So you're telling me, that getting a 10-game chat restriction, 25-game chat restriction, 14-day ban - all of which come with warnings that your behavior is unwelcome, and especially on the 14-day ban, a warning that any further misbehavior will result in a permanent suspension of your account - and then ultimately a permanent suspension...Are too severe, and that Riot is obligated to renege on punishments that you earned for continuously flouting the rules you agreed to?
If you can't be bothered to play by the rules - and that bar isn't all that high, either - Riot can't be bothered to have you playing at all. You may not like it, and you may fundamentally disagree with it, but them's the 8r8ks.
If you can't handle a large volume of requests then maybe this is the wrong industry for you?
I think it would be better to pose that, if you can't follow Riot's rules after multiple warnings that your behavior isn't in line with them, then maybe League of Legends is the wrong game for you.
I understand the need to have the banning feature be automated, but if a player takes the time to appeal it, it should be manually reviewed. EVERY. SINGLE. TIME.
Even if all of the counterflaming cases got manually reviewed, the punishment would stay in place, because as mentioned above; neither Riot nor the community wants people who exacerbate flame wars.
if your automated system is allowing premades to exploit it and get players unfairly punished...
Premades can't exploit the IFS. The IFS doesn't care how many reports are filed - it just checks to see if at least one has been filed, and if so, it reviews the behavior of the player in question. It's a boolean flag; if reports == 0, no review. If reports > 0, review.
And again; you are entitled to your opinion that counterflaming should not be punished, but that doesn't mean that that's the case. Counterflaming is punishable, and it is not an unfair punishment.
...after they just spend that entire game bullying the player, maybe riot could be a little responsible and manually review the case, and punish the correct players?
If you were being bullied by a premade, and you flamed back, then "punishing the correct players" would involve punishing the members of the premade who bullied you, and you as well.
On top of that; if you want to see someone punished, Report them. It's as simple as that. Don't waste time with waiting after the fact to send in a Support ticket to ask for a manual review and to have the other players punished - report them in the post-game lobby and the IFS will handle them.
As of now the system is totally busted.
Considering that you carry the misconception that the IFS can be abused by premades, I don't think you can really call the system busted. It has its problems, sure, but the actual problems it has are far different from the ones you think it has.