Not really, no. Astro requires you to opt a component in to client-side rendering, React (with its server components etc) require you to opt out. Defaults matter in scenarios like this and I'd bet the average developer of crappy websites would have a much faster site with Astro than React for that reason alone.

Small correction: it's other frameworks that require you to opt-out, most notably Next.js. Although I've been seeing so many people confusing Next.js with React lately...

Astro itself works just fine with React, and it can still be HTML-only.

But you can also render React on the server yourself using renderToString, if you don't want a framework.