That's a very technical perspective. If you're a note taker, you ALREADY write in a format that is comfortable for you. And like the vast majority of people who enjoy putting proverbial pen to paper, you aren't thinking about bloody html tags.

The goal of generators is to reduce the friction of taking your notes/articles/etc. and wrapping them in thematically consistent HTML/CSS for your site. Once you've got it tuned/setup for your blog, they're pretty easy to use.

Obviously in your use-case where you find static site generators more complicated, then you can stick with raw html.