Just because they set the bar low, doesn’t mean it’s not still intellectual superiority to step over it. The fact of the matter, as you pointed out, is that they were taught everything you’re about to say in elementary school. The fact that they didn’t learn the earth is round implies there’s more going on in their head than a lack of information.

I’m inferring from your tone that you’re not planning to compassionately listen to their perspective to provide constructive criticism. So yeah, it sounds like you’re going to spend a few minutes calling them stupid. Which has no benefit other than stroking the intellectual part of your ego. It actually will likely make the world a worse place, because you’ll present yourself to them as someone they don’t want to be like. Further entrenching them in their views.