Read 'Black Family in Slavery and Freedom' by Gutman.
There are many metrics by which the black family is doing worse now than it was during slavery. E.g. Teenage pregnancy and female headed households have gone up, with a large spike from the 1960s. Black teenage unemployment was also lower than white teenage unemployment for several years in the 40s.
It can be debated what impact slavery has had, but slavery cannot be blamed for the reversal of these key trends.
That does nothing at all to undermine the point. Why would you expect them to do better after centuries of being taught to obey and strict separation and major disadvantages that still last? Recently I watched a lecture exploring the long-term public health consequences of apartheid ion South Africa. The blacks had been deliberately - and I mean as conscious government policy laid down in papers - taught to live a dependent life, obey the authorities, not think for their own. So of course you get horrible results now that they are "free". You think that proves something about them? When people say "it's cultural" as if that means "it's genetic" - that "culture" also is the result of the policies and treatment they received over the centuries.
Why would you expect them to do better after centuries of being taught to obey
The insinuation that a reason blacks don't do better because they are trained or bred to be obedient is pretty gross, and not that different from the racist "docile negro" rhetoric of a century ago. Why not start with expectations that anyone can better themselves, regardless of race? If you want someone to move up, do you think they have a better chance of doing it if society tells them the can, or they can't?
You've made about ~8 points which would take longer to address than I currently have to spare. I suggest you read 'Black Family in Slavery and Freedom' as well as Booker T. Washington and Thomas Sowell's work. Their scholarship is infinitely greater than any summary I could provide.
