See https://en.wikipedia.org/wiki/The_History_of_White_People where "white" has been expanded and contracted to mean whatever was politically convenient at the time. This is obvious to anyone with even a cursory observation of contemporary American culture. Barack Obama is "black" even though he's equally "white." Keanu Reeves is "white" even though he has an "asian" parent. Argentinians are "hispanic" despite being light skinned and descendent from Italians and Germans, why? Well they speak Spanish. Even the fragility of whiteness illustrate this fact.
This whole "race realism" is the same discredited scientific racism that has persisted for hundreds of years, and is this is the second (and far more virulent) time this has come up in my adult life. The only twist on this very old idea is that now the "smart asian kid" stereotype throws a wrench in the works, when before you you dismiss asians as a bunch of treacherous lazy opium addicts. Now you have to put them in on a near peer to whites, but but discount them as "smart, but not imaginative. Good followers, not leaders." The whole thing obviously is there to simply reinforce existing stereotypes, and reduce humanity to entries in the D&D Monster Manual.
Even in this forum, and this very thread we've got a guy pointing out this out completely with citations, and he's modded down to oblivion because of the actual racists in this forum (themgt, JPKab, wutbrodo, wallace_f, and no doubt others, including those hiding behind throwaway accounts) find it uncomfortable.
So in conclusion, fuck the fascists.
"This one study from 1976..." isn't a convincing case for establishing that link.
If there were a good meta-analysis that tied together several studies and made a reasonable, statistically-grounded case that race is tied to IQ, while simultaneously explaining the contradicting studies, the anime-avatar Race Realist crowd would be absolutely tripping over themselves to post it.
Where is it?
https://en.wikipedia.org/wiki/Race_and_intelligence
That said, I don't think anyone is arguing we should resort to genocide, segregation, eugenics or any of those previous "solutions". I believe people are arguing that unless we can talk candidly about factors for the growing divide, we will never fix anything.