I have a lot of blue collar friends, and I think the point he's really making is that there are a lot of men who aren't cut out for higher education or technical school. It's not that they're not capable people, but it's that they think very concretely and it's difficult for them to grasp higher education because of all of the abstractions. They can be taught to perform tasks, and some of them have people skills that are good enough that they can lead teams, but they will never be computer programmers unless we commit as a society to put in decades of work per person.

These are men who would be farm labor in another era, except that we mechanized all of that. Or they might be steel workers in another era, except that we mechanized all of that and then shipped it overseas. Many of them are tradesmen or warehouse workers and will be mechanized out of a job in the coming decades.

It's not that they don't have anything to offer, but it's that as a society we no longer have a productive use for them.

Honestly, I think a lot of them will become more involved in child care than their wives over the coming decades, and I think that that transition will be hard for us as a society. The only other alternative I can think of involves us colonizing the Moon or Mars, because those are the kinds of places where men like these shine.