Your reports system is flawed
I enjoy how there's a "negative attitude" report option for if somebody isn't "positively contributing" to the environment of the game verbally.
Yet there is no option to report for a last pick person picking Pantheon for support, grabbing flash and ignite despite the request of his ADC that he is supposed to support being he at least take exhaust. This Pantheon then taking farm, hitting minions to make it difficult to get farm, repeatedly leaving the bot lane for minute on end to sit in mid - not just gank, sit in mid - borderline intentionally feeding the bottom lane, not communicating with the ADC in the slightest bit, and not even bothering to build any support items or invest in wards until the very end of the game as a token "look I bought a ward I must have been doing it all game" gesture.
And despite my support doing all of this the entire game, I am expected to just sit there and bare it. And then on top of that, not only must I simply deal with the fit-throwing support, I'm also completely unallowed to report him for any of this besides, at most, "refusing to communicate with the team", which you, Riot, don't do a thing about. And when your team starts being incredibly toxic towards you, you also aren't allowed to say anything back, you're not allowed to leave and remove yourself from the situation entirely, no - you must sit there. You must play the game. You must deal with your entire team putting you further behind on purpose and with them intentionally allowing the enemies to dogpile you without so much as an attempt to help. You must sit there and you must deal with it and there is absolutely not a thing you can do about it.
And yet I'm the one who gets to be reported for saying, "This guy isn't even trying to support me. What am I supposed to do?", with the reply coming from my mid - who has just given the enemy LeBlanc another kill - "Shut the fuck up" along with my top saying the same thing. And that report is the only one that will be conidered.
Your reports system is the most flawed piece of crap on the planet.