I've heard of Gordon before, and I've understood his important point to be less about innovation and productivity, and more about the remarkable historical and technological circumstances of post-war America and the associated economic growth that Americans tend to accept (insist?) as de rigueur.

It was a perfect storm of capital, values, and scientific progress, but notably, it has never been seen before and it is unlikely to last forever.

I think because comfortable (say, median income or better) Americans literally cannot even imagine how uncomfortable things can actually get (or how uncomfortable they actually are in some places) these conversations tend towards unwarranted optimism.