With the level of technical knowledge we’ve achieved, there’s no way we’re going back to doing things exactly the way they used to. One example that jumps out at me is the method this primitive technology guy on youtube uses to stoke his furnace. He’s basically made a little manual turbine out of leaves and vines to push his air rather than one of those little squeeze box things.
Obviously I’m not a blacksmith or historian so I don’t actually know how common something like that might have been, but I’m guessing it’s not super old. In any case, I’m sure there are other ways that we’d apply our more advanced knowledge to tackling the sorts of problems we’d be looking at with a collapse of manufacturing and shipping infrastructure.
Honestly, a technologically adept but non-industrial society of artisans sounds kind of cool.
To be fair, I can close my eyes and just sort of flail on an elliptical in a way that would absolutely hurt me if I tried it on the ground. It’s also a lot lower impact and when I’m done I can just stop.