I think it's worth separating out different tasks in terms of how g-loaded they are (that is to say how much they require intelligence).
General life success is g-loaded but not to an extreme degree. As many have noted, it's certainly possible to have success without great intelligence by working around one's limitations and finding other strengths.
But consider other tasks like "invent a new theorem in particle physics and get it published in a top journal" or "improve a mature database/load-balancing system to save a million dollars a year for a large computing company". These are extremely g-loaded tasks. Intelligence, as measured by IQ, is an absolute requirement to be able to do these things at all in my opinion. My sense is I don't think anyone could ever do such things without scoring 120+ IQ at absolute minimum and probably much more, though I'd be happy to hear counterexamples.
That's an example I'd say where intelligence as a concept and measure is useful in narrow strokes: When you need such a task to be done and done well, you can use intelligence measures to filter who does it (the same way you'd use stature to filter who you put on your basketball team).
In any case, however useful intelligence is, it's the most useful of all psychometric measures. Everything else is worse. That makes it not a great tool necessarily, but the most generally important among the tools we have.
General life success is g-loaded but not to an extreme degree. As many have noted, it's certainly possible to have success without great intelligence by working around one's limitations and finding other strengths.
But consider other tasks like "invent a new theorem in particle physics and get it published in a top journal" or "improve a mature database/load-balancing system to save a million dollars a year for a large computing company". These are extremely g-loaded tasks. Intelligence, as measured by IQ, is an absolute requirement to be able to do these things at all in my opinion. My sense is I don't think anyone could ever do such things without scoring 120+ IQ at absolute minimum and probably much more, though I'd be happy to hear counterexamples.
That's an example I'd say where intelligence as a concept and measure is useful in narrow strokes: When you need such a task to be done and done well, you can use intelligence measures to filter who does it (the same way you'd use stature to filter who you put on your basketball team).
In any case, however useful intelligence is, it's the most useful of all psychometric measures. Everything else is worse. That makes it not a great tool necessarily, but the most generally important among the tools we have.