Javascript must've done _something_ right, no? Yes I know it's bad from "language design" perspective, but we all know what it did right: it was embedded out-of-the-box on a very popular platform (the browser). So, there is an explanation.
Do note that I didn't claim "popularity == quality". I'm not even claiming K is bad!!! Just that it's strange for something so clearly superior to everything else to be such a niche language. Surely it must have downsides...
Why is it strange? Think of languages like Lisp, Smalltalk, Haskell. You may not find them on top of TIOBE, but their innovations do trickle down to mainstream, indicating that the designers of mainstream languages find them worthwhile.
Array languages are very much poised to do the same, if they did not already: numpy is essentially a poor (and verbose) man's array language embedded in python. Or consider Matlab.
> "A LISP programmer knows the value of everything and the cost of nothing."
Here, a very old quote that tells you directly what is wrong with FP - the performance on old hardware sucked. For a very long while compilers/interpreters were not good enough.
The cost/benefit equation changed in recent years, and sure enough, FP ideas are becoming mainstream.
Again, I'm not saying that array languages don't have fundamentally great ideas. I'm saying that articles like this one do them no favor - they're just smug rants. Show the world you understand the downsides, and you get a better chance of promoting the upsides.
More seriously, core language quality is not the primary driver of language choice.
Otherwise we'd all be using something with S-expressions, Hindley-Milner, dependent and linear types. ducks