I don't know, seems somewhat convincing on the surface but goes to mix some interesting ideas and facts with appeal to authority via quotes and a many unsubstantiated statements led by those ideas/aforementioned facts.

The one thing I always come back to is that nobody really seems to go into the definition of productivity - it's roughly hours worked to produce something, but the details are always sort of scarce, even from the FED.

I don't know, 1970 is also about where population growth started slowing.