Emil O W Kirkegaard

No, it is not fat-tailed. Fat tailed means expectation or higher order moments for distribution do not exist (see, for example Pareto distribution). On issue of skewedness, we don't see too low iq types because they die or locked in the institutions.

Fat-tails doesn't have to imply mean is non-existent.

But higher order moment should be non-existent, otherwise it means there is no fat in the tail. And again, we have normality tests, so we can be pretty sure whether IQ curve is a indeed Gaussian.

Could that even be on an absolute scaling? Even if you used a neural network model ( e.g. system of coupled equations), you still have uncertainty induced in the output response. It seems the notion of expectation value makes more sense than a 100% determinism. Imho.