They can - it’s just more complex.

You just put the comments into something like firebase/supabase etc or use one of many off the shelf solutions. Free tier is fine.

Is it still a static site then?

You could just do it with CGI scripts, without the external dependencies, but that isn't really static either.

	▲	Closi 2 hours ago \| parent \| next [-]
		Depends what you would call that architecture then I guess! I run my local theatre website by writing the posts in markdown, and then have some github actions which use Hugo to turn it in to a static site and then uploads the content to an S3 bucket. The site itself has dynamic content like within-website ticket buying from eventbrite and a contact form that sends email using an external service. It also calls in things like google analytics. Does this still count as static? Personally I think so, Even though there are 'dynamic' elements. IMO static refers more about how the content is served rather than saying that the content can’t be ‘dynamic’ as lots of Wordpress sites have static/non interactive content but still regenerate the html on each page load.
	▲	DANmode 3 hours ago \| parent \| prev [-]
		I run static sites for my clients, with embedded forms. Performance says they’re definitely still static sites!

"Just" sure is doing a lot of heavy lifting in this sentence.