A lot of expected pessimistic HN comments that seem to miss the point here. I think SSG's are pretty damn good, I use Astro. People seem to think that SSG's forces you to use markdown or something, they don't. It's literally a mechanism where content from somewhere is turned into static pages. You can even use Wordpress and it's API as the source of the content for a SSG.
In my case I use MDX, which is Markdown that allows components (eg React) to be embedded. This is great for interactive content, articles with charts, visualisations, etc.
Thanks for posting! I update that blog post regularly to keep up with all the possibilities. Ironically, I decided to remove the comments from my own blog a few years ago. Comments still reach me, though, mostly via email.
With something like Astro you can use React (or others, even vanilla) components that can either be fully server rendered, or sent to the client. With that you can allow people to post comments. As for how to render them, depends a bit on what you decide. You can either have comments displayed the next time the site is built, or you could have a posted comment trigger a build, or some other similar idea.
In my case I use MDX, which is Markdown that allows components (eg React) to be embedded. This is great for interactive content, articles with charts, visualisations, etc.