it depends on the person, it seems like a racist comment to me, he called mayweather, and guards all african americans monkeys, called khabib a backwards cunt for not drinking, i mean not all people are the same, some people are not gonna take these kind of strong insults and just be cool which is perfectly understandable.
this video kinda explains it.
In Ireland monkey is not a racist term. We'd often call white people gym monkeys. But again your best come back seems to be "oh mcgregor done it too". Well guess what i never said mcgregor was an angel.