I think the vast majority of the Flynn effect was moving the bottom up, not moving the top up, so I don’t expect the Flynn effect to be super important here. Relevant quote from Wikipedia:
Some studies have found the gains of the Flynn effect to be particularly concentrated at the lower end of the distribution. Teasdale and Owen (1989), for example, found the effect primarily reduced the number of low-end scores, resulting in an increased number of moderately high scores, with no increase in very high scores.[15] In another study, two large samples of Spanish children were assessed with a 30-year gap. Comparison of the IQ distributions indicated that the mean IQ scores on the test had increased by 9.7 points (the Flynn effect), the gains were concentrated in the lower half of the distribution and negligible in the top half, and the gains gradually decreased as the IQ of the individuals increased.[16] Some studies have found a reverse Flynn effect with declining scores for those with high IQ.[17][13]
I think the vast majority of the Flynn effect was moving the bottom up, not moving the top up, so I don’t expect the Flynn effect to be super important here. Relevant quote from Wikipedia:
Interesting, thanks.