It started as SSG only but they added SSR so yeah they're now in the same space as Next, Remix, SvelteKit, etc. In fact Solid's creator has said Astro is proba

It started as SSG only but they added SSR so yeah they're now in the same space as Next, Remix, SvelteKit, etc. In fact Solid's creator has said Astro is probably the best way to do SSR with it.