I have teammates like this:
Seriously, doing nothing but self harm entire game just because things didn't go your way. I'd be totally okay if it was just in game ranting and people would have spine to accept some guilt... but they literally go just ape-shit the second even one teammate starts raging, and then your lane isn't doing well, or they get more than 1 death. It just turns into complete rage fest and there's really no cure.
It's been like this ever since season 1, but it's been getting worse and worse. Occasionally I have great teammates that the matchmaker decides I should get in my team and we got easy wins. Then we got some autistic dude who guy punched in the face in school or something and all they're doing to do is try self repair their image by being asshole in the internet.
I recently took Aurelion Sol as Jungle role, yeah it's crazy I know. I had good clear, good jungle sustain, always warded, never got killed in invade, I happened to have highest KDA in whole team in end of game. I ganked all lanes all the times, but our top lane just went %%%%%% after 3-4 minutes in and mid laner soon joined because he was getting killed by enemy Vladimir (one of the easiest to gank lanes, right?).
I feel like attitude wins like 95% of the games, and if it's not those 5% attitude doesn't kill the game, it's the fact like 50% of games I got a feeding lane that can't stop feeding, if I'm a jungle...
But when it's that 95%, like everything you say has to be like talking to bunch of kids in kindergarten, you have to be talking in so good manner. IF someone says something nasty you have to coach the whiner and the one who is the target. But at the same time you have to keep playing as well and not keep typing. Sometimes talking to them like they are trash might help as well if they truly are irredeemably terrible, but then you get banned from trash talking. Its the the games nowadays need a special coatch for every single game when there's always some autistic person that goes ballistic.
Yeah i'm not giving any solutions here... I guess best way to climb is to be popular streamer doing smurf account and then sharing the stream every start of game, telling those idiots to stop blaming and them being "exposed" to "pros" helps them to feel like they need to play their best.
If you watch recorded LoL streams the players are just far worse with their attitude, which explains why pros climb up so easily... just my 50 cents.