Choosing between a static site, a server-rendered site, and a browser app
Three families
Static. Files built ahead of time and served from a delivery network. Fast, cheap, nearly impossible to take down. Suits brochure sites, documentation, blogs and landing pages.
Server-rendered. The page is built on each request. Suits personalized content, changing inventory, and anywhere the content depends on who's asking.
Browser app. The browser runs an application that fetches data separately. Suits systems with rich interaction — dashboards, editors, internal tools.
Choosing without fashion
Ask three questions: how much of the content is identical for all users, how critical it is that search engines see it, and how much interaction is on a single page. A brochure site built as a browser app pays for it in load time and complexity without getting anything.
You can mix: most of the site static, one area dynamic. That's usually the right answer for content systems with a personal area.
What changes in maintenance
A static site rarely breaks on its own. An app with a server needs monitoring, security updates, environments and load handling. The gap in operating cost over a year is far larger than the gap in initial development.
Going deeper
In mixed systems, clearly separate content built ahead of time from data fetched at runtime, and set each its own caching policy. Most “stale data” problems in production come from caching layers piled on each other with no single policy to decide.