I've been developping two websites for more than a year, both pure react web apps, one of them having millions of users per year. Both had the particularity to

I've been developping two websites for more than a year, both pure react web apps, one of them having millions of users per year. Both had the particularity to use Netlify's one checkbox prerendering button. They are heavy computing websites, Google was ranking them in red on lightspeed SEO, since it's now detecting that users are served différent HTML than to crawling user agents. Then we switched to Next, with some "use client" / RSC headaches we moved some heavy computing to provide most of content to Google/users with a good performance, 75-100. 5 months later, still no SEO impact. Curious to get your SEO measures if you followed the same path. Then one website was shared on a big media. SEO went x2 with noticeable keyword changes. Content, refering websites >> supposed SPA drawbacks. The only major advantage of Next to me, aside from being a good framework (but composing React + Webpack + ... is good too), is generating good social share metadata, notably Vercel OG images. TLDR : you're developping a blog ? Use Next with RSC. You're developping an interactive Web app ? Use React + prerender and avoid all the server side rendering headaches, or use NextJS with top levels "use client" and "SSR: false" for some components like maps. Just use Next as a PWA with some server side bonus, and worry about perf later, when you have a audience.