Many well-designed proportional fonts have fixed-width numerals (if not by default, then available as alternates) to address alignment.

I don’t think tech writers necessarily use monospace fonts for good reasons—most likely they’re simply accustomed to it, and it doesn’t occur to them that there’s something better out there.

And this isn’t just about superficial appearances—I focused on poor legibility because it’s a readily apparent detriment to usability, but there are plenty of other things wrong with programming languages—enough to fill a book, which I should probably write. Strictly imperative programming, for instance, is a degenerate style of problem-solving that forces developers to exert far more effort than necessary to get the same amount of work done. Haskell is better, and more productive for me, than any procedural or object-oriented language I’ve used.

Thanks for the comments, though. I really appreciate this kind of long-form feedback because it helps me improve my future writing.