It's definitely not just skin color.

I know a tall skinny guy from India. His skin is actually black, so black it looks sort of blue-black, not brown at all. He has black wavy hair, also jet-black. He has an aquiline nose and thin mouth.

He's very bright, he has a PhD from a top university in a technical subject.

He says he's of the same race as white people even though his skin is black. It's very clear he is not of the same race as sub-Saharan Africans.