hey thanks for linking to routerino <3, i;ve thought about using something like this for my vanilla react projects and this seems perfect.
do you know what are the actual downsides for the end-user/client when compared to SSR (besides requiring client js)?
the main downside as a developer is it can be a little more work to set up Prerender depending on your hosting setup (although Netlify has just a checkbox to enable) to allow Googlebot to view the page JS-free. I've been playing around with some ideas to eliminate that requirement, however.
as an end user, the only downside would be the typical SPA ones, such as the client needs to render the site with JS like you mentioned (except in cases where we use pre-rendering).
https://www.npmjs.com/package/routerino