My general impression is that people haven't changed much, and the American "can-do" spirit is alive and well. There are some problems with zoning laws, and many folks are financially clueless or even irresponsible (don't have savings accounts and such), but to me the limiting factor seems to be capital.
> Your complaint is that people are effectively being paid the same as those prior generations.
I think you might have gotten confused by how the article uses "the same purchasing power" in a few places. It's actually saying (and again, I Am Not An Economist) is that gains from increasing productivity have not gone to the middle class.
In any event, my point is that if people had more money they would build more.
I don't find the "cultural stagnation" thesis very compelling.
Also this whole statistical view of people is flawed. For the kinds of jobs where increased productivity should go to the worker, perhaps it did, and we call them rich now and move the goalpost to exclude them.
As for cultural changes, if you compare to other countries there are clear differences today. I think of government participation broadly as a "theraputic" institution. You contribute to something larger to make yourself feel good. This could mean building things or cleaning up trash etc. In the US however, for the last few generations this disproportionately means vote/protest for social progress agendas (in the eyes of the citizen), such as to impose "fairness" or lifestyle change. People's civic energy is basically channeled into just drama as the fight goes back and forth producing nothing.
Your complaint is that people are effectively being paid the same as those prior generations.