First, no, Asian countries west of the Khyber Pass are treated as white/Caucasian. In the 1970 Census, Asians all the way to Bangladesh were treated as white/Caucasian.

Second, and more important, lumping South Asian in with East Asia is due to demands from South Asians in the 1970s to make them eligible for minority privileges such as low interest SBA loans.

This is the Big One of this line of thinking—blacks are the Most Diverse—but I’ve never seen an example given of how this could be useful in regard to African-Americans, who tended to be highly blended. It would be important if, say, African-American descendants of the Shona Bantu tribe tended to have significant medical differences from African-American descendants of the Ngala Bantu tribe, and individual African-Americans could check off a box to tell you that.

But, first, there aren’t all that many big genetic differences among Bantus. Second, Bantus and Bantu-adjacent West Africans contribute the great majority of the sub-Saharan genetic heritage to American Descendants of Slaves. Third, the real exotics among sub-Saharans, such as Pygmies and Bushmen, are vanishingly rare among ADOS. Fourth, virtually no ADOS is an unmixed descendant of any one Bantu tribe.