In many of the visual examples, the recommended approach looks worse than the criticized approach, and in some cases is much less parsable. A phrase like "Use more whitespace" isn't some simple-yet-woke millennial web mantra, it's just crappy advice, too vague to be useful and vague enough to be harmful.
Truly, some of these examples are the antithesis to good design. The chapters of the book seem highly opinionated and forcing a particular set of (unvalidated) opinions upon me instead of generalized, objectively applicable tools.
Many an engineer-designed page or screen would have benefited from some of the basic principles here, including "use more whitespace."
Also, as a rule, don't listen to HN for design opinions. Many people here talk about design like a bad programmer talks about principles: "Always have 100% unit test coverage" or "Functions should never be longer than 7 lines".
My recent favorite was when an article introduced an unusual, award-winning checkbox design for a very specific use-case, and a number of comments completely missed the context [1].