I don't think the purpose of SSR + hydration is to simply move the wait time from first render to server response, or that servers can somehow render faster. To fully yield the benefits you'd have to enable caching, so that the server spits out something without rendering and the client side can simply hydrate.
Caching is not something individual distributed clients can do, which is why the server is the only way able to reasonably take on this role. You can also easily configure nginx to serve just-in-time caching.