In large part this was because paper was incredibly expensive back then, so it got used for one purpose, used again for another, and that continued until you were out of room ... at which point it may get used yet again (for say mummy wrapping).

Another classic example: Jews believed you couldn't burn a piece of paper once you wrote the name of God on it, so there were special towers in ancient cities for Jews to throw away their paper. But again, because paper was so expensive, each paper often had lots of other things on it.

Because these towers were sometimes preserved better than libraries were, historians have found huge treasure troves of saved papers in them. Like the mummy wrappings, they only still exist due to a special quirk of ancient peoples ... but because of the price of paper they have lots of other non-mummy-wrapping/non-God's name stuff.

Frankly I can understand that: Homer really did smash out an absolute banger with Iliad. I might ask for a copy in my grave too, when the time comes.

The whole point of the article appears to be that when civilizations overlap, the "good old days" becomes a two way street (to gargle metaphors). I do find that interpretation very interesting and it fits in with my world view that history ("historia" - Latin for "story") is generally rather more complicated than many would like it to be to fit their current (or current as was) world view.