> It seems like maybe they didn’t pay in enough - baby boom demographics meant there were relatively more productive workers paying for relatively few old people, so each worker was paying a fraction of what it would cost to carry themselves through old age.

Right but manufacturing technology better and more efficient, we produce far more "per worker" now

Yeah, but I don’t think we’ve seen commensurate gains with healthcare workers, except by perhaps reducing visit time per patient.

Perhaps the inference is that the owners of industrial technology should be paying more taxes on their profits, since the proportion of labor as an input is shrinking.