Being born into a rich family certainly has its benefits.
Your dismissive attitude makes me think though... if those 66% of African-Americans turned out okay... why does the problem of single-parenthood then persist through generations? What is the factor that makes so many African-American families stop working over time?
Without having done any research on the African-American population this sounds a lot like the same self-sustaining problem we have in German low-income areas (at least those dominated by native Germans and non-Muslim immigrants): Single-parenthood leads to people who have not learned how to live as a family and then become single-parents when they're older.
Alternatively, people who grow up with separated parents are less likely to believe that marriage is unbreakable (or that splitting up will ruin their children's chances in life), and so will be more likely to leave an unhappy relationship than let it run on and make everybody miserable. I'm certainly not convinced that two parents who would clearly be divorced except for a sense of obligation are any better than one who is reasonably happy with life.