Did Riot eventually sort out the toxic community? If so that would be amazing, and definitely relevant. I stopped playing when it was still there, and it was a big part of the reason I stopped.
Recently picked it up again and I noticed that I didn’t had to use /mute all anymore. I’ve got all-chat disabled by default so I’ve got no experience there, but overall I’d say it has come a long way.
But I’d also say it depends which mode and MMR you are in. I mostly play draft pick normals or ARAMs in which I both have a lot of games played - I heard from a mate that chat is unbearable in low level games.