Pretty sure there is a behavior elo to everyone's account and it plays a role in matchmaking
As a serial flamer that has no intention of ever stopping my flaming or shitting on kids in low elo, I've noticed one thing through my 25ish account journey that really makes it impossible for people like me to reform. Riot gives you tilt streaks just like they give you wins streaks. Its one thing I've noticed from countless times of trying to reform, I can just play the game as usual for a month, couple of months, 2 years my first time, you get one tilt streak and its over. How is it that I managed to never get any punishment for the first two years I played this game, but ended up banned permanently within two months of that initial chat restriction. How is it that I went two years punishment free but now cant go more than two weeks? Well, its partly because of the overall trash and declining quality of games in the past two years but I believe its also because ever since the honor system rework that whole prisoners island thing Riot says they would never do has been happening behind the scenes. Eventually you get a streak of matchmaking with such degenerate trolling idiots that will send you into such a maddening rage you will get restricted/banned or just plunge deeper into the bad behavior elo.
I have noticed hundreds of times that when making a new account I start to remember the names of people I play with throughout the week. How is it that I'm a "new" account playing with other new/low level accounts and I see certain people so much I begin to remember their names and have conversations in all chat with them picking up from the last game we were in together? Not to mention I have started asking recently how many are chat banned or trying to restore honor and its like 80%. From what I have seen, once you get some reports on your account its doomed unless you literally just don't ever interact with people in the game. I'm almost certain Riot uses the reports you get from people + honor + some other easily tracked stats like how much someone types in order to assign people a behavior elo.
Once you get some reports or a leaverbuster warning, you get the nonstop afks, you get the kids with meme/racist names that troll non stop, you get the people who follow you around your jg and just beg you to flame them, you literally just get bombarded with ridiculous circumstances that call for telling the people how disgustingly degenerate they are and then you go deeper and deeper into the bad behavior elo pit until you start getting punishments. Its a positive feedback loop where behavior gets way worse over time. Take me, two years no chat restrictions turned into 2 week account flame master.
My latest account got banned because literally 3 games in a row I got the exact same troll kid that trash talked endlessly, when he was support he even followed me around the jg and tried to steal camps for the first ten mins. Three games in a row with this dude, I'm not challenger why is the system matching me with this asshole 3 games in a row after we constantly flamed each other throughout all the games? Its simple, riot claims to not do prisoners island style grouping but they have literally all the systems set up for it. They have the number of reports, your honor level, how much you type, how many censored words you type, how many pings you do, so many other stats. Its so easy to just matchmake based off this and that explains exactly why the player pool for low level silver/gold skilled players is so low that I get 5 minute queue timers and can recognize the names of players from previous games.
Its cool if Riot is doing the whole prisoners island thing, just dont gaslight the fuck out of everyone and try to make it seem like you dont. Pretty WeirdChamp.