In general the oil and coal being extracted today can't be reached without the huge inputs of already-established energy infrastructure and industrial machinery - all the stuff that could be reached with hand tools and a mule were cleaned out long ago. If the present industrial society goes down, the remaining fossil fuel reserves are out of human reach effectively forever. Any surviving human remnants will have biomass and sunlight to work with, and will mostly have their attention occupied by the task of wringing enough food to survive from a severely damaged ecosystem.

We would need global socialism very soon to pull off a planned, controlled simplification and localization of supply chains and dependencies and draw down to a less delicate economy that provides simple but dignified standards of living.