This is such a weird false-dichotomy you're portraying. No one is expecting you to weigh in on arcane/abstruse things. This is about a current holiday in America that commemorates freeing of slaves ~150 years ago, not slavery in the Mycenaean civilization of 1100BCE.
You said you're not American - ok then maybe you should've stayed out of the thread entirely? But since you didn't, then you should realize it is your responsibility to educate yourself. Like just plain and simple: can you imagine a police officer policing a foreign people being unaware of their history/culture/etc?
Like can you imagine the same thread about mistreatment of aboriginals in AU - would you similarly blithely claim ignorance? Indifference?