Well most people don't blog. We just don't have that much to say.

I hope that is not true. I think it is more a matter of organizing your thoughts into something you deem presentable to an audience. Maybe the Dunning-Krueger effect explains the generally low quality of many blogs - Potentially high caliber bloggers are overly self-critical and don't publish, for others the converse.

Maybe. There are a number of things I don't find original enough to be worthy of a blog post or don't have enough data to feel comfortable saying. There are a few rare things but they fall under the terms of the exclusive lease my employer has on my brain.