They certainly do, but for they same reason why people chose static site generators like Hugo over Wordpress, I'd like complete control of full data.
The good value of static-hosted comments is that you `git clone` for backup and `git push` for redudency.
I also dislike managing DBs. Think of all those mess with backups, migrations, imports, exports, difference between mysql/pg/sqlite/d1. Tons of operating cost just for the sake of few blog comments
It's just a bunch of .jsonl files, the last resort is direct inline those .jsonl into .html files when generating