It's not just immigrants from Africa or those who share their racial identity, but its also, and probably more importantly, about the lineages who were kidnapped from Africa as slaves and their families who were stolen from for generations which left very little in their communities to pass to their present day ancestors. It's not good enough to have black faces in high places, because there are people who have been systemically destroyed and their visibility is being obscured by those who happen to look like them. We don't need to give even more opportunity to relatively wealthy African immigrants, some of whom hail from families who profited from American slavery.
There are many parallels around the globe but the point is that there is a lot of nuance to consider if AA is to be effective at what I think was the original intention was: to increase equity among those marginalized for the sake of creating a system most closely resembling a meritocracy.
I'm not even sure there's a single 'original intention'. Political projects are always pushed by a coalition of people, everyone with their own agenda.
