Again, I'm not sure why you're telling me this. This is a significant part of the thesis of the article. I'm well aware of it. But many people aren't. Which is why I wrote the article.

But again, yes, many IQ researchers make exactly this argument. Lewis Terman made this case numerous times (including arguments for segregation and eugenics). So did Nicholas Wade. And Charles Murray's latest book "Facing Reality" (whose work I have read), is about his belief that racial disparities will always persist because of the differences between the "races." If they will always persist, if we just have to "face reality" on this point, that suggests that he's talking about genetics, no? Culture and environment can certainly change.

And no, the truth of my statement don't simply depend on the last clause. It depends on a fundamental lack of understanding of genetics that allows one to categorise all people with brown skin as similar, whether you mean genetically or culturally. I'mnot genetically or culturally similar to a black person living in Kenya. Or Namibia. Or Zimbabwe. They aren't similar to each other. Using this superficial similarity to categorise billions of people is silly whether it's Asians or black people or white people.

Wilfred Reilly does a fairly good job of criticising those arguments here (https://www.commentary.org/articles/wilfred-reilly/charles-murray-facing-reality/), but there's much more out there.

I'm not sure how you could have spent any time looking at the discourse regarding race and IQ and not heard people (not just members of the public or outright racists but some researchers themselves), claiming that these differences are genetic. Never, it's worth noting, with any evidence.