The big component libraries in Javascript are +10 years old (except for Vue.js, which is "only" 7 years old), everything else that came afterwards is just a rehash/horizontal iteration as you say, be it Next, Gatsby, or Remix. If you learn e.g. React well, using any of these frameworks is fairly easy.
Which is kind of cool IMHO; this means the core libraries remain the same and then the ecosystem improves around. It's a world of a difference between React early days manual setup, the big advancement that was Create-React-App, and then again some other minor but amazing leaps like esbuild or vitejs. I can setup a fully-featured React app and be productive in seconds, with amazing nice things to have that traditionally had to be manually configured in other languages (linter, transpiler, hot module reload, etc).
Which is kind of cool IMHO; this means the core libraries remain the same and then the ecosystem improves around. It's a world of a difference between React early days manual setup, the big advancement that was Create-React-App, and then again some other minor but amazing leaps like esbuild or vitejs. I can setup a fully-featured React app and be productive in seconds, with amazing nice things to have that traditionally had to be manually configured in other languages (linter, transpiler, hot module reload, etc).