I would bet money that the "inferior" trope started when white folks realized that those who were able to survive slavery were so much obviously smarter and stronger than the white assholes holding the whips that they used the word "inferior" as a defense mechanism.

It stands to reason to me that anyone who survived middle passage and/or slavery had to be damn smart, resourceful, tough, strong, all that. It was probably pretty intimadating when the slaves got freed.

If anyone is inferior, it sure isn't Black folks.