Well, it’s the end of the day and I need a post because CRUNCHYCHRISTMAS. So here’s a thought.
Maybe social virtues such as group altruism are eventually part of g (maybe at mean IQ > 110, leading to group selection). A natural environment which supports “group” level g, as in k selection, tends to be more and more specific as g increases (cold but not too cold, having a loving mother but also lots of anxiety from life stressors). Therefore it is more fragile to changes in the environment, because for instance even slight warming disproportionately favors R shift. So if you think of an R and k spectrum, then raising “group” g will require pushing the band of possible supporting conditions toward the k end, but also make it thinner.