I like APL (and k/j). Problem is, outside trading (and even there it's a niche), it is just not popular enough. This also because most people dismiss it as line noise / write only programming language; that's usually only people who never used it or used it briefly saying that. But it's hard to promote anything that has a reputation like that.
What is a fairly interesting observation (more people have made it, including Arthur Whitney); being able to reason about a program for which you can see all the code on one A4 without having to clickthrough into functions, search, browse through files, classes or even having to scroll is incredibly powerful. All you need is the cheatsheet (provided in your article) (which you know by heart in no time flat) and the program, which, often fits on 1 A4 or less. Modern example of that would be Aaron Hsu his 17 LoC parallel APL compiler[0] (from his thesis).
What is a fairly interesting observation (more people have made it, including Arthur Whitney); being able to reason about a program for which you can see all the code on one A4 without having to clickthrough into functions, search, browse through files, classes or even having to scroll is incredibly powerful. All you need is the cheatsheet (provided in your article) (which you know by heart in no time flat) and the program, which, often fits on 1 A4 or less. Modern example of that would be Aaron Hsu his 17 LoC parallel APL compiler[0] (from his thesis).
[0] https://www.bonfire.com/co-dfns-thesis-edition/