Emancipation could declare formerly enslaved Black people legally free, but society had been structured for generations around the belief that Black people were inferior. Therefore, abolishing slavery did not instantly cause society to recognize them as social equals.

Yes. That is a historically meaningful argument.

And there is very good evidence for it.

The Library of Congress describes the post-emancipation situation as one in which formerly enslaved people were legally free but faced “many hostile whites”, and it records a freedman's observation that white people did not know how to have a free Black person “about them.” It also documents the subsequent emergence of segregation and racial violence.

Even more directly, Giuliana Perrone's scholarly article argues that abolition was a long and complex process, because simply changing positive law could not erase the lived and institutional legacies of slavery. She concludes that slavery's effects continued to shape the lives of former slaves after abolition