> It feels like there's an unexplored dimension of abstraction here. Something where generics, interfaces and higher order functions are too static and low level primitives. Something where it's really difficult to pinpoint what exactly is the repeated pattern here and how to exploit it. Instead of generic framework that can do everything, I'd like an efficient way do something specific.

This bit reminds me a lot of a concept Aaron Hsu mentions in his fantastic talk on anti-patterns in the Iversonian languages[0], a paradigm he terms "Idioms over Libraries". The idea being that because of the expressive power of APL's primitives programmers often opt for utilizing easily recalled snippets of symbols over the importing of library code to implement common functionality. This facet of array-lang culture can be seen with sites like APL Cart[1], which serve as indexes of these frequently used snippets.

I think a lot of people miss that this is one of the major advantages induced by the terseness of these languages (it's not just about code-golfing for the implicit joy of laconicism). By allowing for the direct expression of algorithms in the same context they are being used, APL and its kin enable one to tweak and optimize these idioms on a case-by-case basis: precisely the kind of specificity the author of this article is asking for.

[0]: https://youtu.be/v7Mt0GYHU9A?t=1027

[1]: https://aplcart.info/