Dans gist is referring to needing a routing layer to map something like `/blog/my-latest-article` to `/blog/[article].html`. This is the same of any non-React SPA.
If I have `pages/blog/index.tsx` in my NextJS app this will get output to `blog.html` and can be deployed like a static site without further top-level routing.
My original comment was specifically in reference to dynamic routes.
You're referring to static routes.
This is not the same as any non-React or non-Next SPA either way. A lot of them have SPA support i.e. route anything to index if there is no match. They may not have random rewrite support though.