@toolbear See, that’s an example right there, “homogeneously white”, where the word “white” means a very specific thing to Americans in this context which you just go and assume has to have exactly the same cultural connotations to the rest of the world.
And then start using that assumption, or even assertion, to eg tell Roma people that they can’t possibly be victims of racism (and they very much are) because the experience of people ten thousand kilometres away is somehow more pertinent to their situation than their own.
It’s kinda like going to another country and remarking that it’s full of foreigners.