What's the poorest country in the western hemisphere? Haiti. What makes it "special"? Now, what's the poorest most impoverished continent in the world? Africa. What makes it "special"? I think you get the picture.
I interpreted it the other way around, it's easy to get mixed up when subjects are sensitive. He's not trying a deductive argument (which would be trivially defeated by pointing to, off the top of my head, Perelman, and many others one which you also tried), his approach is inductive. He's offering statements about reality as evidence which are consistent with the hypothesis that "black people are stupider on average". That hypothesis was also made and argued pre- and post-civil war in America, along with the prediction that subjecting the freed slaves to the economic slavery of the north was a worse fate because it was possible to work full-time and still not be able to afford adequate living, something we also see more clearly in east-Asian sweat shops today but also more subtly (i.e. the actual conditions are better but real choices and freedoms are nonexistent) all around America.
Another approach to having a useful discussion is "What would the world look like if 'black people are stupider on average' was true, and if it was false?"
Of course his post wasn't careful enough since you still misinterpreted it, it's even possible I misinterpreted as well, but even if I'm wrong I consider my reading more charitable and if you seek a discussion it's better to pick the more charitable one given alternatives.
Of course, you could just flame him as others are doing. Might be better to just downvote and ignore (as many are as well).
If that bar of 'acceptable evidence' is set so that those examples can be used to support the theory that "black people are stupider than average", then my examples of poor catholic countries in europe should be acceptable to support the theory that "catholics are stupidier on average".
There used to be a lot of discrimination against people based on religious groups within christianity. But now catholics are considered white.
