Neil's theory has different empirical predictions than Baumeister's, for example, it predicts high Self-Control correlates with low direct resistance to temptations. On the second Lecture he mentions several experiments that would tell them apart. They are different theoretically, there's a difference in the importance they give to willpower. Saying you should save water on the Sahara is different from saying you shouldn't lose your canteen's cover.

It is surely my experience in life that people highly overestimate their causal effectiveness in the world, and Neil's lectures convinced me willpower is another of those instances.

Evolutionary signals of environmental stability in childhood (that set the levels of future discounting, mating strategy and so on later in life) are more frequent in wealthier families. For instance, there's research on cortisol levels in earlier childhood, frequency of parent's fighting, wealth and adult life criminality, mating strategy and so on. In evolutionary terms, the correlation between status and stability is pretty high.