People are definitely blowing off steam, or at least, in Psychology, they are reflecting off what they are experiencing in real life. The person behind the screen that's being toxic could be a victim of bullying, domestic abuse (like child abuse in the household or something, because I know that the vast majority of this game is around the age group of 10-17), or it could be that the person is mentally unstable in real life. There are many possibilities.
Pair that along with the anonymity of the internet, people tend to be bigger jackasses on the internet than they do in real life. I can easily say with 100% confidence that if I ended up meeting one of the most toxic people in this game in real life, they would be either the complete opposite of a jackass in real life, simply because they can't hide behind their computer screen. The anonymity part is one of the biggest factors on why people are jackasses in multiplayer video games because there is very little to no risk in acting like a complete jerk to someone who you'll probably never meet in real life.
But still, there is absolutely no justification for being a complete jerk to someone on the internet, let alone someone you have never met in your life. You can report those kinds of people for verbal abuse and hate speech. If they do it enough times, then they'll get banned, though, that too has very little risk in League, since they can just make a smurf account and continue the toxic trend. Riot should seriously take a page from Blizzard for some type of player moderation. Blizzard may be draconic and strict when it comes to player moderation, but their Overwatch community is easily one of the nicest, and one of the more pleasant communities I am glad to say I am part of. I suck at Overwatch, but I don't hear people screaming at me through their mics, and I don't see people taking 10 seconds out of their lives to tell me to kill myself, unlike here in League.
