SEO is like gravity-it doesn't care what framework you use to build the ladder. The bots just want clean HTML, fast response times, and a crawl path that doesn't dead-end.
Someone in the thread mentioned Spring Boot as a backend joke, but the point stands: pick the stack that lets you sleep at night. If Next.js makes your content pipeline smoother, great. If plain React with a static export does the same, also great. The ranking difference between frameworks is noise compared to the signal of a slow server or broken sitemap.
The real bottleneck is almost never the frontend library. It's the server response time, the JavaScript that blocks rendering, and the lack of meaningful internal links. Solve those, and the framework becomes a footnote.