On the other hand, there are big holes in these stories. Economists who spend a lot of time talking about getting people into college do not, on average, spend a lot of time talking about how to make colleges better at teaching students. And while it’s true that some people may not be marriage material, or have bad luck in finding good partners, and will feel even worse if we tell them that this is also going to make them less happy, rich, and long-lived on average than married people, it is also true that some people aren’t college material, and others will fail to graduate due to bad luck or poor decisions. Won’t they also feel bad if we keep telling them how awesome college is?
Which makes me gravitate towards a more parsimonious explanation: all economists are, definitionally, very good at college. Not all economists are good at marriage. Saying that more people should go to college will make 0% of your colleagues feel bad. Saying that more people should get married and stay married will make a significant fraction of your colleagues feel bad. And in general, most people have an aversion to topics which are likely to trigger a personal grudge in a coworker.