Interesting mental exercise. It was explored in A Canticle for Leibowitz[0], novel in 3 parts (Fiat homo, fiat lux, fiat voluntas tua), the first set in the immediate post nuclear-war world, second 600 years after towards the end of the new middle ages, and the third 600 later in a typical futuristic scenario. The first part covers the religious efforts to preserve knowledge (even if said knowledge was not understood), and the second in the new renaissance from wielding such knowledge.

I wonder how LLMs, with their mistakes and all, would play a role in rebuilding civilization. Most media these days is not prepared for staying stable for 20 years, not sure how much and for how long it could be preserved. Perhaps mechanical hard drives in certain isolated environments?

https://en.wikipedia.org/wiki/A_Canticle_for_Leibowitz