One of the reasons I like fairy tales, and liked them as a kid, is that they follow certain rules. The cruel, the greedy, the evil are punished in the end. The good, kind, honest, and hardworking are rewarded. Suffering is generally not in vain. And while death happens, often the parents of the good kind protagonists are described as dying peacefully after a long, good life. In other words, it portrays a world that seems to me more just than our actual world. (Too often in this world, it seems to me, the cruel do not see the consequences of their actions, and the fact that “no good deed goes unpunished” is a saying tells me this world is less just than it could be.)
I’ll go a little farther with that: the examples of justice being meted out, of heroes triumphing over frightening foes, are absolutely essential for young folks. They have to see that it’s possible to survive something scary, and that wrongs are eventually righted. There’s plenty of time for them to become cynical once they become teenagers.
And now that I think about it, this may be my true rock-bottom objection to Equestria Girls: they took half a dozen examples of Equestria’s finest, who have stared down (literally, in Fluttershy’s case) some of the scariest scenarios known to pony, and dropped them into a remarkably ordinary suburban high school. This is about as useful to a kid’s development as sending Andersen’s Ugly Duckling to the mall for a makeover.