> I'd note that there are many studies showing that the usual outcomes for gifted kids are not all that great.
No, there's not, and they do do great. And this goes back to Terman: there's a handful of highly selected examples (eg the Australian kids recruited from child psychologist referrals, the self-selected self-diagnosed Mensa adult survey), furious anecdotes, and then every systematic prospective sample like Terman or population registers or SMPY shows the opposite.
And while Tao is, of course, exceptional, the results for accelerated gifted kids are generally great. And Tao was part of SMPY (note the URL path, supporting documentation for https://gwern.net/smpy ) and helped demonstrate this in practice.