As Next ambiguously puts it: "The React Framework for Production" [0]
It's excellent for building page-based sites and apps and comes with lots of nifty features that just seem to work. And, the most part, it's just out of your way.
Regarding the ideal use, I'd say any project that benefits greatly from (partially) pre-rendered content and statically generated pages is best served by Next and its data fetching [1]. I can't think of a FE-based solution that is anywhere near as good. It's also the only sane way to work with the insanity that is JAM stack [2].
Looking at the razor pages overview & that seems a very reasonable comparison (now you mention that, see PHP, in the form of "just chuck a few files on a server that understands them and off you go, dynamic website")
It's excellent for building page-based sites and apps and comes with lots of nifty features that just seem to work. And, the most part, it's just out of your way.
Regarding the ideal use, I'd say any project that benefits greatly from (partially) pre-rendered content and statically generated pages is best served by Next and its data fetching [1]. I can't think of a FE-based solution that is anywhere near as good. It's also the only sane way to work with the insanity that is JAM stack [2].
Whatever you do, it's a safe bet.
0 - https://nextjs.org
1 - https://nextjs.org/docs/basic-features/data-fetching
2 - https://jamstack.org