The problem is that we have no theory of intelligence that tells us
what, if anything, IQ is actually measuring.
If you renamed IQ to "linear-correlated ability to take non-domain specific tests", or "GTTQ" (general test-taking quotient). Then you'd explain every observed correlation between IQ and non-IQ performance.
So, do businesses want intelligent software engineers, or those with a high GTTQ score? As research at google, iirc, has shown: high performers on coding challenges tend to do worse in practice.
Any plausible theory of "competent software engineering" would, I think, place an extremely minor emphasis on a GTTQ. Intelligence is a much richer phenomenon (need for cognition, curiosity, resilliance to failure, domain-specific depth-wise thinking, cross-domain lateral, etc.)....