Astro ships zero JS by default and only hydrates the interactive islands you mark. Next.js ships a full React runtime because it assumes an app, not a document. For a content site that split is the whole decision: Astro for mostly static, Next.js when interactivity is the point

fetch() doesn't reject on a 404 or 500 — only on network failure. So error handling that assumes a throw will silently pass bad responses straight through. Axios throws on those by default and adds interceptors, which usually determines the choice.