This kind of highlights the true threat of a "dark ages" period. That's defined as an era where not only is the ability to do certain things lost, it's forgotten that we ever knew how to do it in the first place.
Mankind is ever on the verge of another dark age. Even today there are monumental tasks that our grandfathers and great grandfathers accomplished, that are effectively impossible now. At some point they regress into mythology. More than one librarian spends sleepless nights worrying about bitrot and expired internet domains causing critical information to be lost forever. Could we build the saturn V rocket again? The Boulder Dam? Why is there a resurgence in the publication of books about how to live independently on your own land without technology, using "lost arts" that everyone used to know as a matter of daily life?
