because writing HTML manually is fucking terrible compared to authoring markdown. We (i.e. everybody) are trying to improve things because they are bad.

I mean, I agree that incremental improvements are great but also I think your hyperbole is a bit of an overreaction. I use markdown and templates and Software people rightly prefer reuse and DRY principles but handwriting html is honestly only barely a notch more primitive.

HTML files can't reuse anything, HTML is a pretty bad verbose language, it is hard to keep indexes and links up to date when you change your site, and well, a lot of other reasons that I didn't think about because I gave-up on that in the 90's.