Comment by bluGill

In the ideal world, assuming this is true, we could then ask for the question of, well, what can we do about these people with different intelligence levels?

Intelligence is not just a single thing. We can assign a number by an intelligence test, of course, but there are lots of ways to look at it that are more nuanced. Generally, you're not going to say someone is better than everything you're going to find that someone is better at some things. And so can we direct people to the things you're better at for the better of everyone? Division of labor is a good thing.

But contrast, assuming that we find it's not true, then we can ask, well, why are we finding these differences in the data? if it's not genetic and perhaps we can find what it really is and then improve those groups that are currently disadvantaged.

The larger point is you have to know before you can make a useful adjustment.