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IQ is a deeply questionable metric to start with (I have yet to see good evidence IQ tests measure anything more than "how good at IQ tests you are", and as a child I obsessed over them and got very good at them by learning how to approach them, which means it very much isn't measuring something innate), tests are often (and in the case of the historic ones actually cited in the "evidence", all) culturally biased, an…
See, for example, Schmidt, F. L., & Hunter, J. (2004). General Mental Ability in the World of Work: Occupational Attainment and Job Performance, cited 1600+ times:
> The psychological construct of general mental ability (GMA), introduced by C. Spearman (1904) nearly 100 years ago, has enjoyed a resurgence of interest and attention in recent decades. This article presents the research evidence that GMA predicts both occupational level attained and performance within one’s chosen occupation and does so better than any other ability, trait, or disposition and better than job experience. The sizes of these relationships with GMA are also larger than most found in psychological research.
One main reason why you might not have seen this is that you didn't go out of your way to find it, and the mainstream publications systematically hide, distort, and often blatantly lie about the existing evidence.