They basically invent a special new type of mental impairment to apply to brown people to sidestep the need to explain why entire swaths of the global south aren't desolate wastelands of barely functional people trying to converse in grunts, as predicted by Lynn's research.
That the statistics of a mean IQ of nothing imply that you should be able to fit every current African university graduate in a room together seems pretty valid as a reductio ad absurdum of the whole affair, surprised I didn't see it mentioned before.
They had 3 kids last time they came up, which despite their posturing is not really a notable amount, and they're both nearing their 40s, so it's unlikely they'll hit quiverfull numbers.