I think they fail to explain the majority of the behavioral differences. Specifically, they fail to explain:
1) why the children of upper class parents do not start behaving like poor people when they are broke (e.g. during college or grad school).
2) why Mexicans make good choices like sneaking into America, working hard, forming stable family units and saving money.
3) why Indians make the same good choices even when they don't have the option of sneaking into America.
4) why unskilled Chinese immigrants (or folks back home) make the same good choices.
Of course, if people internationally can be "the best", then perhaps domestically people can be "the best" (or not) as well. For example, perhaps bad inner cities and Trump-voting rust belt regions are full of people who are very much NOT the best.
I think you're agreeing with me.
I think it's true and can explain behavior that is both self-destructive and selfish. To solve the problem you have to figure out how someone like that can get themselves out of the vicious cycle. Even if they are morally deaf I don't think much gets accomplished by focusing on that point.
Add to this the fact that certain behavioral strategies may seem self-destructive from one perspective but necessary from another. Drug use for example has nasty consequences but is frequently a mechanism for coping with some other very nasty problem. And you have... well, I don't know what, but a complicated world.
I am not saying Trump supporters are all jobless drug addicts but I absolutely think lower education, lower income demographics swung toward him because they have more direct experience with the dark side of modernization and the political establishment was tone deaf to this.
(Also, of the factors I mentioned I think the lack of college degree is the one most heavily correlated to lower income, lower employment, higher addiction, higher unintended pregnancy etc. not which city they're in.)