I think this argument, and OP (sorry) is among the dumbest discussions we have on the SDMB. It belongs in mini-rants, maybe, but who is seriously put out because someone on occasion might say, “I prefer to be called ‘x’?”
It’s the Golden Rule, people. If you were traveling and someone called you Canadian when you are in fact American, you might not feel the need to correct them every time. But perhaps you would on occasion, and it wouldn’t be a big deal, if the person simply heard your request and complied.
I don’t care what you call me when I’m not around, but I find the term “African American” and “Black” equally fine. Nor do I know anyone - and I know a lot of Black people, from all political views - who would be offended if you referred to them as either of these if you were pointing them out in a crowd or meeting them for the first time. That doesn’t mean that they won’t correct you and say, “I’m Cape Verdean,” “I’m Haitian,” and so forth. But offended? Not so much.
If you know me well, you know that I am half West Indian (Jamaican) and folks on that side of my family are Jamaican, not African American. My gramps who lives in Canada is of course no way African American, but in the most liberal use of the term. But again, no offense taken if you are describing them phenotypically and are using the ethnic descriptor. If we’re associates or friends then you should know better, but again, I wouldn’t get offended, and I daresay nor would any other reasonable person. Now if you respond with some variant of “I don’t give a shit,” then I can see why people might give you attitude.
Bottom line, how hard is it to call people by what they wish to be called, realizing that you will encounter the occasional learning moment when you make an assumption that’s incorrect, and move on? It sounds as if some people would like an algorithm for interacting with human beings that are different, and that’s a little lazy and ridiculous.
And just because there’s people out there who don’t mind being called “fat,” “skinny,” midget," “beanpole,” or “homo” does not mean that everyone feels the same way.