Glad to hear you loved it. That's a good point about the extent of the material decline, and the impact that would have on the most-societal scene.

However, we should consider the egalitarian aspect of prehistoric hunter-gatherer tribes. The postapocalyptic novel Earth Abides suggests that a return to the nomadic lifestyle, which would entail low tech and bare subsistence would free the tribe of survivors from the social climbing needed in the civil dominance hierarchies. It would be a return to a childlike phase of animistic wonder.

Of course, we shouldn't think the Stone Age was idyllic or utopian. But I'm not sure the dichotomy between modern progress and prehistoric primitiveness works either.

I suspect the post-civilizational phase would be something new, some mix of naivety and jadedness. In practice, I suspect, the parasites and predators would likely spoil the creative potential, and we'd be back to mafia-like monarchies.