Search and editing. HTML is a pain to maintain. In this day an age, dynamic content is more suitable. Imagine if many news websites (like the Associated Press) were done in straight HTML. You would have to have a webmaster(s) maintaining it 24/7. Coding HTML is not easy over time. I've coded HTML back in the days and eventually I moved to a template format for my HTML pages. Eventually, it was a pain to add content because I would have to code entries by hand and if I made mistakes, then I would have to go into the page, look for the error, correct it, reload the page, wash, rinse and repeat. Eventually I switched to a more robust system using databases. Editing content became much easier since it involved less coding. Formatting issues became less of an issue. And the big gain was searching. Now I could search for keywords, or articles that were posted instead of following link after link after link. That's the advantage of going that route.
But as Mr. March said, his site, his content. He'll edit what he wants to edit, when he wants to.