Is the American IQ study controlled for race? Gen X and millennial immigrants had more selective pressure, so they were more likely to be among the most intelligent of their home countries, leaving a brain drain in their wake. During Gen Z the overall rate of immigration increased; illegal, unvetted immigration increased; and the standards decreased, so Gen Z nonwhite immigrants in America aren’t as intelligent as the older ones. That and the overall lower percentage of whites in Gen Z account for the decreased IQ scores.

It would be more enlightening to know the generational IQ scores of only white Americans. If we remove the factors of demographic change, we can more likely pinpoint the effects of technology, educational practices, etc.

I’ve read before that Peak Flynn was the cohort born in 1975.