That is categorically untrue. Verbal cultures in Australia have kept an accurate account of a coastline that existed over 10,000 years ago.
Meanwhile, the supposed collective knowledge in books is constantly second guessed and taken with grains of salt ("bronze age army sizes couldn't possibly be the size they write that they are", "the winner writes the history", etc).
Meanwhile, the supposed collective knowledge in books is constantly second guessed and taken with grains of salt ("bronze age army sizes couldn't possibly be the size they write that they are", "the winner writes the history", etc).