How many African-Americans truly wish that their family had never left Africa? How many African-Americans would give up their life in the USA to return to Africa?
See? Lots of good came out of Africa. Millions of people were able to grow up somewhere else -- somewhere where they could have a better life, with opportunity and freedom. Shame about the slavery, though.
Well, a lot did return - that's why there's the terrible mess called "Liberia."
I don't think that's the issue. Of course African Americans are truly American, not African, and never do they realize it more than when they actually go to Africa. (Ditto for those of us of European origins when we visit "the old country" -- whichever one our ancestors came from -- and I'm told it's also the same for Asian-Americans.)
So the point is that African Americans don't wish that their family had stayed in Africa. They would have liked their ancestors to have left Africa, sure, but of their own free will as most of our ancestors did. Sure, most immigrants endured hardships, both in the passage and once they got here. My ancestors came from Ireland during the famine and were despised by the "Native Americans" -- but they were FREE. (My Irish ancestors were also able to retain their religion and cultural traditions, which the slaves were not -- the imported Africans were stripped right down to their names and their knowledge of their heritage -- but that's another story.)