This is an interesting thread question. What I would note is that most dramas of necessity are in reality dramas in costume. What I mean is that they generally reflect the attitudes, assumptions and behavior of people in a particular sociocultural context. We don't recognize the costume aspect of dramas if they are of our time and place. But this is why they age quickly because the next generation looks at those people in those funny clothes and hairdos having those stilted conversations and wrinkles up their collective nose. This is why fairy tales and weird stories last longer because they sort of stylize these dress and behavior features and add certain aspects outside everyday reality to them. Thus they stand outside normal time.