...which makes TOTAL SENSE in terms of ancestral geographic distribution, way MORE sense than "black" does--both designations assigned, incidentally, by those same caste-desiring racists.

The genetics can be viewed a variety of ways, but for this purpose this diagram of human genetic diversity and ancestry works well: https://www.nature.com/articles/s41598-017-01837-7/figures/2. Note how all the "white" peoples are clustered together towards the tips of the tree (part B, around the center right), while the sub-Saharan African groups all branch near the base of the tree (on the left), indicating their dissimilarity to each other.

You have got to come up with a better argument, if you're going to maintain this position.

This one is so wrong as to be exactly backwards. "Black" is a ridiculous racial category genetically because it contains the widest genetic diversity (thanks to the origins of our species in Africa); "White" actually makes a decent amount of sense in terms of lineage (until you start deciding which "multi-racial" people get to count as "white", and then nonsense ensues).