Lets first separate ethics, "political correctness" part of it. The problem with g factor is that it's more or less innate, like height. So companies have to avoid doing IQ tests as such, and psychometrics measures something correlated instead like inductive/deductive thinking abilities.

As for "IQ does not correlate" with CPS - there are studies, eg https://www.psychologytoday.com/ca/blog/brain-candy/201306/study-is-complex-problem-solving-distinct-iq and metastudies, and yes, average correlations found are about 0.43 see https://www.researchgate.net/publication/282247397_Complex_Problem_Solving_and_Intelligence_A_Meta-Analysis

(of course, there should be nuances and direction of causation, but we are talking correlation here)

Software companies can use programming challenges as a substitute. And of course complete programming noobs are not employable as lets say senior software developers. (there are some seniors who are offended by taking any challenges, but that is a different story).

I do not claim IQ should somehow totally determine employability. The person can be toxic (I wish there were studies on correlation as well for this!), motivated in the wrong way (job just for money, side project of interest), etc. Plus it is not clear what is the bar? Is 130 ok for a software developer on this specific position or 115?

As for being a good parent, it's also kind of inherited thing. Somehow thousands of ancestors were not complete dummies because we live today. (ironically, intelligence is about adaptability to ones environment as well.)

And the topic of the article is also wider. Are psychometrics ability tests useful at all in hiring or trash? And in which cases? Is it useful for pharmacists, pilots, surgeons?