Here's the problem with not just LoL's but every game's report system
Every game's report system ends up being used as a tool for retaliation and as a threat because there isn't a way currently in most games where they actually tell the player making the false reports that they need to cut it out and that there will be consequences.
This is the same in CSGO, Dota, Cod, etc.
Sure, league takes away report weight if you make a lot of false reports, but I highly doubt that they know that they're making false reports and that their report weight is being lowered. So they keep using the reports as a threat, and that brings even more toxicity to the game.
They don't know their reports don't matter, so they'll keep on with their toxic witch hunts saying "report Master Yi feed pls" in all chat and just starting those report bargains like "you report Yi and I'll report Akali" rather than legit reporting.
INSTEAD OF PARROTING, CAN YOU READ? I AM NOT SAYING THAT THEY'RE DOING NOTHING TO VERIFY REPORTS. I'M SAYING THAT PEOPLE WHO FALSE REPORT SEE THE REPORT SYSTEM AS A WAY THEY CAN BLAME PEOPLE, THEY DON'T CARE IF THEIR REPORTS DO ANYTHING. THEY JUST WANNA BLAME SOMEONE, AND THAT'S TOXIC IN AND OF ITSELF.
This is what I said and this is what I mean "You know that most people who false report, report not because they believe it will do anything but it makes them feel good to blame someone else for a loss? The system itself is just enabling these people, they don't care if their reports do anything. They just want to blame someone, and the system allows them to blame someone and feel good about it by not punishing the false reporters. That's bringing forth toxicity."