Implicit is the presumption that the smartest people optimize for wealth, or that the smartest people are good at optimizing for wealth. Outside of Wall Street, "smart" people - academics, doctors, lawyers, engineers, etc. - are just as likely to make bad personal finance decisions and/or to stay in labor (rather than management) positions for most of their careers (leave aside the dual-track IC/management ladder at…
Are they really smart then? You are using a straw man fallacy by redefining who’s smart.
And is who “really smart then”? I knew plenty of people in college who were of similar general IQ as me but chose career paths specifically to maximize income (finance, largely). And I knew plenty who were smarter than me who went into fields such as education or PT/exercise science because that’s what they wanted to do.
So it doesn’t surprise me in the least that IQ correlates with high income to a point, but beyond that point other factors (largely desire to be wealthy) play a larger role.