Marginalium

Historical IQs are made up, and other IQ myths:

just based on his actual academic record I would estimate that … [by correlating test scores to IQ] … Einstein’s IQ was therefore probably more around 120 or 130 than 160. Indeed very high! But maybe not even “genius level.” He would have scored similarly to Feynman, one of the few geniuses we for sure have a modern IQ for, which was “merely” 125.

and

the studies correlating IQ to genius are mostly bad science.

and

Practice works wonders for IQ tests

and

“IQ is one of the most valid and reliable psychological constructs.” And this is true… by the standards of psychology. Don’t mistake this for being what a normal person would refer to as “reliable.” In the field of psychology, almost nothing is reliable. Effects regularly cannot be replicated, and those that can inevitably decrease in their effect size, often shrinking to the barely observable.

(see also the scientific ritual)

and

given its known measurement variance, IQs mattering less and less at higher scales almost has to be true, since the variance alone injects huge amounts of noise into any study. From a statistical level it would be shocking to get really clear results differentiating any real-world factor between IQs of 130 vs. 150, simply because the error is so large, and the number of people even satisfying those conditions is so small

but importantly

it’s one of the only measurements we have that does an okay job at capturing intelligence, in that it’s not too bad at this when it comes to the center of the distribution, although it gets increasingly bad at it at the tails.

The question then becomes, for the centre—just what is IQ measuring? That’s the thing that’s questionable.