But, as you say, in technical writing, it's enormously irritating. I do a fair bit of freelance writing, and it pisses me off no end when editors and clients change a technical term for an apparent near synonym because they don't understand the nuance. It makes the sentence nonsensical and makes me look as though I don't know what I'm talking about.
Any level of nested parenthesis is fine (is what I think at least (as someone who's written a bit of Lisp of Lisp (or Racket and Clojure specifically) (because you get kinda used to it (when in a way they just become invisible (or unnoticeable))))). But nested quotations is also an issue with backtick (`) when doing command substitution in the shell, and we have to resort to $() to fix it. There's not really a $()-like syntax for written English though.
There sort of is, if you use "smart" quotes. “Hard to find on a phone keyboard though, and not that distinct.”
Parentheticals in English sit in this sort of midpoint between a modifying clause for necessary elaboration and a footnote/end-note for optional detail, and lots of people including me use parentheses where "inlining" the parentheses or moving them to a footnote would be more appropriate. That's in addition to conventional uses of parentheses, like to expand abbreviations.
* Nested parentheses. (In theory, you could use any level needed (provided that they make sense), but in practice, they're scoffed at.) It is similar with quotes, for the same reasons: limited readability - although here you can at least juggle with single, double and French quotes, depending on the language and style guide used.
* Repetitions: unless used as a stylistic device (in poetry, advertising, etc.), your editors will try to modify repeated words, trying to find synonyms. In technical writing, it is an abomination, and competent editors know very well they must not touch any specific terms, no matter how often repeated, as they have very precise meaning.
But in general, the rules present in style guides are meant to ensure consistency and uniform reading experience, so that the reader is not distracted by form and can concentrate on the meaning, so they are a good thing as long as people are aware these are just arbitrary rules separate from spelling and grammar.