It's a measurement of cognitive performance, nothing more. It does not tell if you can do a good job or not.
I think it's a good tool when looking a two groups or looking at performances over time.
But it could be biased, for example when he say PhD IQ fall when enrollment is higher, measuring the quality of the work would've been better.
Also IQ don't give you any hint of causation. Maybe IQ drop because of school quality? Screen time? Physical activity drop? Some widespread chemical? Lack of oportunity given the world environmental crisis?
I think it's a good tool when looking a two groups or looking at performances over time.
But it could be biased, for example when he say PhD IQ fall when enrollment is higher, measuring the quality of the work would've been better.
Also IQ don't give you any hint of causation. Maybe IQ drop because of school quality? Screen time? Physical activity drop? Some widespread chemical? Lack of oportunity given the world environmental crisis?
There are many factors that could play a role.