Is Riot's ban hammer automated or is there someone actually reviewing the bans?

So basically, I got perma-banned for mentioning a certain word. However, this word was completely out of context and wasn't in any way related to anyone in the game or even plays League of Legends for that matter. Also, I'm pretty sure another player said the same word.

Here's what happened, briefly.

Enemy player throws an 'ez.' Big woop. I joke back and say something like, "watch out bud, I'm gonna spoil Captain Marvel for you."

Then, we proceed to talk about that movie and then the upcoming Endgame movie. He asks if I'm going to watch it on day of release. I then proceed to say something like, "yeah I have to, otherwise (insert certain word) will spoil it for me." And then they say "just avoid social media," which then I respond with, "but also, I go to work with a bunch of (insert certain word)."

Now before I continue, I do acknowledge that the word I said isn't a good word to say in general.

But back to the case; I personally wasn't aiming any hostility at anyone in the game. So in return, I personally don't understand why it was as harsh of a punishment. I've played the game since beta and I've probably spent more money than I should've spent on the game (several thousand), so I know what's expected of a "model player." It's just in this situation specifically, I did drop some foul language, but I don't think I received fair judgement.

P.S. I would post the chat that I was presented to when I logged on to see my perma-ban, but it shows the word so can't really show it off here.