When I was a census enumerator, if someone had said their race was "redbones", I would have written it down and passed it along.  The checkbox would have said "some other race", but the notes would have said "redbones".  To get accurate data, you record people's responses, without biasing them.  I'm pretty sure that such a respondent would only have been tabulated as "some other race", but their self-identification as "redbones" would have been available for people designing the questions for the next census.  Well, it would have until now -- possibly literally today -- when it probably would have been illegally deleted by some Trump-administration minion as part of their war on reality.

Identical twins don't necessarily have the same DNA.  The criterion for being identical twins is that the two people started from the same zygote.  But many people are chimeras, having some maternal cells as well as cells descended from the zygote.  There's also the possibility of a mutation happening early in embryonic development, with the relevant population of cells being derived from mutant cells in one twin and unmutated cells in the other.  Of course, it's also true that environmental factors can affect pigmentation.

thank you

Quote (10:24):
"... there's an objective difference between hydrogen and helium, and it's the shape of the molecule ..."

Come on.  Everyone learns this in middle school and again in high school.  It's the number of protons in the nucleus.  Helium doesn't have molecules, and a hydrogen atom is still a hydrogen atom when it's part of different molecules in water or petroleum or DNA.

"We didn't decide that we're humans"

Were Neanderthals humans, or were they a closely-related non-human species?  We have decided the latter, even though there's nothing about Neanderthals that would justify it.  In biology, there's no definition of species.  Instead, there are species concepts.  None of the plausible species concepts justifies calling Neanderthals a different species from modern humans, and yet they are, because we've arbitrarily decided.  There is no possible predicate that could be more we-decided-it than our species is.

Mills died of cancer in 2021.

If there is a diversity, there is a hierarchy, one cannot be a racialist without being racist while being intelectually honest

You seem to be under the impression that edge cases prevent robust generalizations. That isn't true as species have edge cases but species are real etc. Very poor effort.