That's the default in rails (view API and data API are the same controllers/shape using accepts headers). It's a mistake for anything beyond a basic data model, and maybe even for that.
Read the blog linked above and the other articles linked from it, I explain the HATEOAS problem in more detail. JSON APIs are moving away from REST and towards a more RPC-style model, e.g. GraphQL. The industry is finally getting sick of shoe-horning JSON into a conceptual model that makes no sense for it.
Anyway, intercooler is a different, simpler way to build web apps. If you are willing to split your data API out from your web app API, you can save a lot of complexity in your stack. We built a reasonably modern web app with it with no front end engineers, just a couple of gronky full stack guys with some rails experience, and not much more code than a normal rails app would require. We built our data API using Grape, rather than rails. Turned out very clean, decoupling the two.
Yes, I am aware that I am telling you almost exactly the opposite of what almost everyone else does and that I appear insane.