Not that there isn't some merit to McIllroy's criticism (I know some of the frustration from trying to read Knuth's programs carefully), but at least link to the original context instead of a blog post that tells a partial story:
https://www.cs.tufts.edu/~nr/cs257/archive/don-knuth/pearls-...
https://www.cs.tufts.edu/~nr/cs257/archive/don-knuth/pearls-...
(One of the places where McIlroy admits his criticism was "a little unfair": https://www.princeton.edu/~hos/mike/transcripts/mcilroy.htm)
BTW, there's a wonderful book called “Exercises in Programming Style” (a review here: https://henrikwarne.com/2018/03/13/exercises-in-programming-...) that illustrates many different solutions to that problem (though as it happens it does not include Knuth's WEB program or McIllroy's Unix pipeline).