Let’s say a genetic test indicated a 90% chance that a child-to-come would be troubled with obsessions and unhappy and unsuccessful, and a ten percent chance that the child would grow up to be one of America’s leading entrepreneurs. Or more modestly, in the positive scenario the child would be comparable to a worker or a scientist who creates $5 million in social value a year. I believe most parents would feel uneasy about this genetic lottery, even though its expected social value is unambiguously high. Telling the parents that the expected value of the child for society would be high would not distract them very much from the costs of the risk.
As I see it, many upper middle class parents desire their child to be slightly more successful than they are, and in related but not identical fields and ways. They certainly would be happy if their child turned out to be the next Bill Gates (and more secure in their retirement), but not that much happier from a parental point of view. Parents qua parents can get only so happy, and if your kid turns out well by your standards you are already pretty close to that maximum.
Notice how children differ from money. Big dollar prizes induce risk-taking, at least from some entrepreneurs who have a strong desire for more and more money. But big “parental prizes,” such a siring a true genius, might not induce much risk-taking with the identities or natures of children.
This is one possible institutional failure if there were “market-based” eugenics, namely that parents would be too risk-averse a social point of view. We would end up with too much sameness, both across children and across the generations, and not enough monomaniacal creators.