It is a little risky assuming correlation - hopefully salary is correlated with a sort of general economic contribution rather than intelligence. Intelligence isn't a prerequisite for contributing mightily.

If intelligence was correlated with salary that would be a symptom of bad outcomes in the economic system. I'd expect that, but wouldn't be happy to see it. Eg, whoever is running the local plumbing small business is in a position to make a lot of money. The plumber might be smart or might not be, really shouldn't matter.

I've seen situations where truck drivers make a higher salary than engineers. More intelligence almost correlated with a lower salary.