Sure there are dependencies, and some technologies will collapse and become unachievable for generations. But others are essentially free of dependencies - the germ theory of disease, the staff system, democracy, air travel, bicycles. Easy to bring back or keep, and with tremendous benefits.
I've always been sad that post-apocalyptic scenarios have no bicycles, and no biplanes. They just postulate people being the same as people were in the stone age, maybe with some recycled trash thrown in.
Consider that food production is very much dependent and looped with all the existing supply chains. As some say, modern agriculture is essentially pouring petroleum into the ground and harvesting crops that grow from it. Could we use our scientific knowledge to get better results than preindustrial people did with the same tech level? Sure. Will it be enough to feed even 20% of current population, especially given the battered climate? I doubt it. And the way I see it, a lot of our "social technologies" - as well as more "physical" ones - seem to depend on population size and density.
Speaking of science fiction tropes, I read an interesting book once - "The Windup Girl". It featured a post-climate-change world with depleted fossil fuels and collapsed technology, that still sort-of worked thanks to machines being powered by mechanical work (with spring systems for storage and special breeds of animals providing muscle power). I wish more books and movies would go into this territory.
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[0] - not just because it's what we'll need come climatepocalypse, but also because I believe there are many unexplored "low-tech/hi-science" solutions that could let us achieve similar results in many areas of life, while using much less energy, or with much less dependence on existing infrastructure. For instance, I feel that mechanical energy storage (springs) and gliders are underexplored and underapplied, since energy today is too cheap to bother.
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EDIT and a tangent: I am really interested in the possibility of combining gliders with computers and sensors to enable extremely energy-efficient (if not time-efficient) flight. If anyone knows of work being done in this space, I'd love to get some directions or resources about it.
Farming is more of a 'trickle petroleum into the ground and harvest crops'. Its one of the most efficient of technologies now. With good timing and no-till and ammonia fertilizer, even eroded clay hillsides produce bumper crops. It is a fragile technology tree but much simpler trees could be forged, having a good whack of the same benefits.
RE farming and other technology trees, it might be worth it to hedge our bets by trying to develop such simpler tech trees right now. In the worst case, we'd be making life much easier for the survivors. In the best case, maybe we could reapply some of those ideas to further reduce energy waste.
Maybe we’ll have a rennasaince. Maybe we won’t; but Paper Books will be critical
If the climate situation gets to the point of crashing global supply chains, say goodbye to all modern technology. Whatever's left will degrade quickly, and we'll be back to preindustrial levels, but with no easily accessible dense energy sources to bootstrap another industrial revolution.
This is why I keep saying that the most important goal right now is not to protect the planet, not to protect the human species, but to protect our technological civilization. If it collapses, we'll still be there (albeit in reduced numbers). But our civilization won't recover for millennia.