You either generate pages at build time from the data or you build a static page that will fetch the data from the client. This means you have zero server side

You either generate pages at build time from the data or you build a static page that will fetch the data from the client. This means you have zero server side rendering, you're just serving up static files, which of course is faster and can utilize CDNs and such. SSR is also still possible, that would basically give you a classic model of fetching data on request and then rendering the page. My impression is that this is meant more as a transition than a preferred option. The SSR features are also optimised to the point that the data fetching and rendering is decoupled. So a client side (JS) navigation only needs to fetch the new page's data. The DX around this is super smooth (just expose an async function...)