There is one study that demonstrated that among top 1% SAT scorers investigated some years after testing, the upper quartile produces about twice the number of patents as the lower one (and about 6 times the average, if I remember right). That seems to imply that having more really top performers might produce more useful goods even if the vast majority of them never invent anything great.

This could just reflect winner-take-all dynamics. Only a few people can get into Harvard. Only a few people can become tenured professors, only a few mentored by major figures, only a few access to resources etc. Success builds on success; if you have a patent, it's easier to get another. A small difference at the beginning (your 'upper quartile') can snowball.

I would bet that being in the upper quartile is only weakly correlated with being smarter than the rest of that 1%. No organized tests like college admissions uses straight IQ, but they do use SAT scores. That says something, I think.