I think of HyperCard as sort of a domain-specific language for a certain UX.

If your application was naturally modeled as a set of records and where you wanted a nice UI to navigate and edit records, it was incredibly easy and productive to get up and running. It's hard to understate how much easier it was to make a GUI app for storing recipes or something along those lines in HyperCard compared to anything out there.

But, like other domain-specific languages, if your app didn't fit that UI style, it got real weird real fast and you felt like you were swimming upstream.