To think a lot of people earning 6 figures aren’t actually that smart, just lucky?

A lot of the time is not smart in terms of intellect necessarily, but hard work, and having the foresight to be in the right place at the right time, by creating those opportunities.

Eg revising well for GCSEs and A levels when others are messing about and partying.
Having the foresight to choose the right a levels / right university to maximise opportunities.
Joining lots of societies / networking instead of drinking (but doing the right amount of drinking to get to know people!)
Securing internships by applying instead of going home to work in a shop

Otherwise having the courage to go for promotions, putting themselves out there.

Simialrly, if self employed, having the courage to take that leap.

Of course, lots of luck will be involved too eg parental help and going to good schools. But all the high earners I know have basically worked really hard for years and years. That is a type of intellect, that’s probably more important in the real world than being a member of MENSA

I think it's more about personality actually. The high earners I know are very non-judgmental (in public anyway) and so are widely liked and respected. They also seem to know when to STFU.

On the other hand, I am shit at these things.