if super-smart people exist, it's fairly certain that some blogs of such people exist. And if such blogs existed, I would expect to have found a few by now.

Why would they blog? They would already know that most people have nothing of interest to tell them; and if they want to tell other people something, they can do it through other channels. If such a person had a blog, it might be for a very narrow reason, and they would simply refrain from talking about matters guaranteed to produce nothing but time-consuming stupidity in response.