Sort of, but not always.

My blog at https://www.silviogutierrez.com is React+Django strictly server side. I like JSX that much. Try loading it with JS disabled.

Same at my business site: https://www.joyapp.com.

It was a huge ordeal getting it setup (with React SSR, etc), but it's definitely doable. I've open sourced it but it sorely needs documentation (incoming):

https://github.com/silviogutierrez/reactivated

Basically, despite the tooling (not because of it), once you get going with JSX, TypeScript and the like, nothing else comes close. At least in my experience.

But again, none of the above stops me from dumping that output into a single cache key per request. It's still dynamic, just cached robustly.