Pay attention to what he says about there being more people in the top 20% than there are in the bottom 20%. He says there are 28% more people in the top 20% than the bottom 20%. That’s fascinating. It’s no wonder that the top 20% make so much more money than the bottom 20%: there’s just more people there, and they are much more productive to society!
Also, pay attention to his explanation of income mobility. That is one of the most fundamental occurrences of economics that I have learned about, and it is extremely consistent. “We are talking about an exchanging mixture of people over time, and not the same people,” in reference to the bottom 20%, as well as the top 20% of incomes. “Many of the people in the bottom of the 20% are the children of the people in the top 20%.” Absolutely fascinating. I don’t know if that was hyperbole or not, but it is still something to think about.