saying the r word is bad and should become less socially acceptable. that being said, i dont think u should be canceled for it because right now its kind of commonly used. so i can see both sides.
Is he at fault for saying a slur? Yes.
Is it critical? No.
What should be done? Noted and ignored afterwards.
I would dare anyone who calls out pros for saying mean words in comms to record themselves communicating , especially during a close game or a game where you are really unlucky. If you say at least one bad word you should delete your riot account and isolate yourself from society
It's different across the globe, in Europe it's pretty much a synonym for calling someone an idiot (at least that's how I've seen it be used in my experience), it's informal and you wouldn't say it to a stranger or someone you've just met, but in other places it's considered a slur. Better to be safe than sorry imo so I'd just avoid it