in sofar as IQ helps predict actual job performance, I'd say yes.
Now I'm not saying the situation isn't complicated. In the mid-20th century, IQ testing was a great driver of social mobility. However, as was pointed out in _The Bell Curve_, it's becoming the opposite. From what I understand, the heritability of IQ and assortative mating (i.e. people marrying other people of similar IQ/educational attainment) are the main drivers of this.
I don't think the formation of an entrenched class system is necessarily a good thing, but I think in the local context of our industry there's still a lot of good that could be done by improving our hiring process. I mean, would you rather hire people who only sound smart, or who are smart?