Why is this historically prominent group of people always left out of historical definitions. Black Americans are defined as the descendants of enslaved Africans in america, but that definition is highly reductive in that it ignores their Free POC ancestry and whatever other ancestry they might have.

What's the cause for this linguistic misrepresentation of the black American ethnic group?

How were they able to live and thrive in the south when slavery was race based? Wouldn't they have just ben enslaved?