Except that for the fact that African-Americans, after being called "Negro" and "Colored" and then "Black" have now decided (most of them) that they want to be called African-Americans.
Fess up, you never cared that the names don't come from
Africa. You were hurt by the racism that the names elicited, and your reaction was to deny that the names exist as a category. You're not the first person to do this and you won't be the last. There's no shame in having things explained to you, you don't have to change the subject to save face.