It doesn’t sound like @XT is particularly open to other opinions on it, but I think he’s just massively underestimating how much stored information we have on physical media and massively overestimating how quickly it would all just “dissolve” into the elements, like we live on some kind of planet that’s akin to Venus where everything just melts instantly without constant interventions.
I’ve literally done house tear downs on homes abandoned for decades where there were still fully recoverable books inside. These were not facilities made to house books, but homes, many of which had been scavenged by homeless people and etc, and this is in Virginia, not a place with the nicest climate (but also not the worst) for preservation.
Certain large cities actually exist in areas that basically should be underwater, and only continual maintenance keeps that from occurring. D.C. and good portions of New York City fit this criteria, and all the water coming in will lead to more rapid building collapses. FWIW, the “Life After People” episode on the Library of Congress posits it would still be fine 5 years later, and 500 years or so later is how long it expected it would take for the big dome to collapse in the Jefferson building of the LOC.
Note that almost every town in the United States with more than 10,000 people has a library in it. Many are “Carnegie Libraries” that were built with masonry and brick construction from the late 19th century that is rugged as fuck, some of these buildings could become forts or defensive positions to be honest.
There will certainly be lots of books decayed and lost, but the scale of the availability of stored knowledge is just not being appreciated, no way all of it is gone. Just about anywhere in the United States you can find enough stored data on books, that if you’re smart and have the time, you could give yourself sort of the basics of a modern day K-12 and even basic college education. More advanced specialist stuff you won’t as easily acquire and replace, but what you’ll have is the frameworks for re-education, which is something previous peoples never had when their societies collapsed.
There’s also going to be wild differences from area to area as to how survival-stressed people are. There will absolutely be areas where people are fairly stable and able to feed themselves within a decade or so, and many of those people will scavenge books for entertainment and other reasons if nothing else. Some of the smarter earliest survivors will scavenge books because they know they lack knowledge essential to survival, and some of these books might contain that knowledge, it is unlikely that they wouldn’t make repeat trips to the libraries–and as I said, in some towns the old Carnegie Library might make a pretty good base of operations, the idea some of these old heavy duty masonry buildings that are built like forts are just going to be devalued and abandoned, and people are going to live in a hole in the ground in the woods when better shelter is available…seems highly suspicious.
I just posit that the survivors are going to be highly focused on growing food and surviving, perhaps in their copious spare time building out local capabilities like steam and electricity, maybe saving some of the stuff in their immediate area. Heck, one of the things they will have to relearn, maybe from books or just trial and error, is how to have kids again. Seems basic, and I think they would be ahead of our long-ago ancestors, but that alone is going to be a real struggle without the knowledge of modern medicine.