A lot of that doesn't look like the kind of thing societies consume, more like the substrate they run on. At least aside from a few crazy outliers like the Khmer Rouge.
I'm having a hard time thinking of policy regimes that require governments to trade off future talent, for example, for continued existence. Maybe throwing a third of your male population into a major war would qualify, but wars that major are quite rare.
Tentatively-- keeping the society poor and boring. Anyone who can leave, especially the smarter people, does leave. This is called a brain drain.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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