Things are not quite that bad - one of the major reasons we studied history over the centuries is we are looking for a way to ensure we will win the next war before the fighting starts. Thus there are a large group of military minded people (both generals and kings) who have incentive to find real truths not the nice folk fiction.

Mostly things are bad, but if you look there are people who did care about the truth - though they only cared about their little niche - everything else they could say whatever was entertaining.