They seem fine for lengthy prose. You probably aren't going to write that many long-form blogs anyway — in the vicinity of several hundreds, maybe. After many years. So that's fine.
But what I've discovered about my writing habits is that I mostly tend to write short notes, about the size of a Hacker News comment. And those can easily number in thousands after several years of writing.
So how well is a static site generator suited for this? Do I want to build thousands of pages every time I start the site locally? I probably don't. But I can't find a reasonable static-site generator that will only build the requested pages locally, and build everything when deployed.
It's probably also silly to pre-generate a static html page for every such short posted note.
What's the most appropriate solution for such a writing pattern? Bite the bullet and set up a Wordpress or a Mastodon instance? That's a bit depressing.