Was the reason of the collaps coming from military conflict? If yes, was that author a winning side of conflict or loosing one or he was enough lucky to stay neytral? Some things will be overexposed or overhidden in any branch.
Was that from global heating? Maybe from deadly virus? From AI? What has been braken, maybe something not important?
Maybe the reader is dealing with collaps of fossil energy industry (no cars, no warm houses and no bitcoin mining, but more important things like science is still there?). Maybe some kind of AI starts being our new government while the half-beaten previous one claims that we need to conquer the AI while in reality it is better government then previous?
Has the author finished his book or died on half-word? How much has the world recovered from the disaster on the moment the book went into right hands - is reader sitting in a bunker or is he is still able to grow foods on his land or is he drifting across a submerged planet like Kevin Costner's character?
Last but not least - if you are destined to be the author of such a fateful book, how can you be sure to describe things both correctly and understandable for your reader?
As for clarity, the Quora thread mentions How Things Work by Roger Jean Segalat, as a positive precedent, https://bibliohaven.com/products/how-things-work?variant=326...
I fear that an attempt to rebuild civilization will lead us to the same mistakes we had made until now.
History has shown that nobody learns from it.