TL;DR, stories are a basic function of the brain trying to understand and streamline reality and they are deathly important because they tell us how to act and who to be. It doesn't matter where those stories come from. Behavior and morality will be stolen from them anyway by whoever needs those because that is the function of a story.

Folk tales always have some sort of moral or warning at the end. Someone who wants to be Cool and Manly and In Control will probably like Clint Eastwood enough to start emulating him. Me, I latched onto the barely-functional moral idealism of The Sneetches as a kid and later to Speaker for the Dead as a teen/adult. All of those are exactly as real as each other, but only one is being labeled in this thread as laughable. If you have a problem with Clint Eastwood, you also have beef with Doctor Seuss.

If we really expected the stories we tell not to influence reality, we wouldn't be fighting so hard for inclusion in media. And that one Steven Universe artist who drew a character skinny wouldn't have gotten death threats