But still with regression to the mean, no? The child of two great geniuses is likely to be a somewhat lesser genius. Above average, but below their parents. A few generations of such regression to the mean and there might not be that much extra intelligence in the descendants of great geniuses.
yeah, animal breeding and crop selection work, but it couldn't possibly work on humans
You are right that the field of genetics is of course applicable to humans, with a lot more muddiness when it comes to the ethics - not the point.
The term "eugenics" describes a certain philosophy/set of ethics which directly grew out of racist narratives at worst and some very loose interpretations of the scientific methods two hundred years ago at best. Furthermore it can argued that the "field" of eugenics never really attempted to shed this, even as of today. Thus, calling eugenics pseudo-scientific is considered fair game. At least that's my understanding.
>Early twin studies of adult individuals have found a heritability of IQ between 57% and 73%,[6] with some recent studies showing heritability for IQ as high as 80%.[7] IQ goes from being weakly correlated with genetics for children, to being strongly correlated with genetics for late teens and adults. The heritability of IQ increases with the child's age and reaches a plateau at 18–20 years old, continuing at that level well into adulthood. However, poor prenatal environment, malnutrition and disease are known to have lifelong deleterious effects.[8][9][10]
* The only relevant factor for predicting chess skill at any level seems to be hours spent on deliberate practice, see for example: https://doi.org/10.1002/acp.1106
* There is the decently famous Terman research (https://en.wikipedia.org/wiki/Lewis_Terman), who was convinced that he could predict future Nobel price winners, executives and wealthy people by IQ-testing them as a child. His approach basically did not work at all - to just name on aspect; he actually excluded two future Nobel-price winners from his group of future winners because their IQ was too low
* Students who are picked to fulfill minority quotas are just as likely to have successful law careers after graduating than their picked-by-intelligence colleagues (https://doi.org/10.1111/j.1747-4469.2000.tb00967.x)
I could name many more, but it is not my intention to win an argument by wall-of-text here, I am genuinely interested in sources pointing into a different direction. Thank you for your time!
This is wildly implausible, and indeed the paper makes no such claims.
No, this is flat out wrong. There has been so much research on this, and intelligence is both highly predictive of life outcomes (controlling for wealth) and extremely heritable. If you take the biological kids of smart people and raise them in poor households, they still turn out very smart, much smarter than the biological kids of dumb people who are raised in rich households.