Eliezer, as you say, you have written hundreds of blog posts. For each blog post, what is, on average, the chance you are wrong about your basic point? If it is even as much as .5%, then you are probably wrong about your basic point in at least one post.

You are overconfident if you claim an accuracy of greater than 99.5%, and you claim that this estimate is calibrated.

You are also overconfident if you do not claim this accuracy, but also do not allow that you are probably wrong in at least one of your basic points.

People (including me) get the impression that you hold to one or the other of these positions, and that is why it seems that you are overconfident.