My problem with K isn't its syntax, it's its culture: People who are so self-satisfied with their ability to read their own code they refuse to give variables meaningful names, aping mathematical tropes they half-understand at best, because those mathematical equations are only tolerable in the context of a paper where the rest of the lifting is done by natural language prose. They eschew comments without realizing that those comments enable terse expressions by showing you have the basic maturity to express yourself in a way others can understand.
Knuth tried to move us to that state with Literate Programming. How many K programmers use Literate Programming? One? Two? Any?