Not saying it doesn't matter but what we have here on this board are individuals who don't deal in nuance and instead probably because they are like cult followers of YouTube personalities refuse to maybe examine their own sloganeering they hock and see if in reality it makes sense. At some point even the cultural heritage of say the grandson of great grandson will start to disappear in the assimilation process and this may be uniquely an American situation. In America, unless you're a new immigrant socially and how you're viewed and treated, you're black, unless it's obvious you just arrived over here from Kenya or something or maybe your parents instilled their culture heavily on you and I argue that influence typically doesn't last past one generation. For example, take the Obama. Obama highlights his Kenyan heritage heavily but I have doubts his daughters who are even further assimilated in ADOS through their mother have the same affinity for that heritage. It seems to dissipate pretty quickly and at some point you have to ask does the distinction outside of being specific really matter as far as how one lives their life.
Though I'm speaking in general I know places like say new York, nationality and specific ethnic ghettos outside of your standard China towns and, err Mexican areas exist and maybe it's a different dynamic there.