Going by the response headers, it seems that most if not all of the HTML served by docs.mux.com consists of cacheable static files. As the OP article mentions, using React for static generation is one of the big use cases for RSC and Next.

Which templating technology would you recommend for the use case instead? Keep in mind that generating HTML from OpenAPI specs can become complex and will require plenty of maps, filters, recursion and indexing into the data in the course of transforming it into HTML.