The author has a strong game development (engine and tooling) background and I have found it incredibly useful.
It also satisfies the requirement for "A genuine fear, hate, and anger, towards unnecessary allocations, copies, and other performance killers."
I am not linking to handmade hero, I'm linking to a separate project of his (his performance aware programming course) that is actually aimed at being an educational piece.
I lied, I will comment on one factual piece. "normal library code in favour of hand-rolling your own half-baked implementations based on outdated trivia." Yes, that is the whole point of the series (not the characterization as half-based and outdated trivia). The point was to show how to build a game (and its engine) from scratch to as big of a degree as possible. The avowing of library code is the point, to show what it takes to build engines rather than call a library so that the industry has more people who would even attempt doing such a thing.
Equally anecdotally, based on available online information, he worked for a long time on core technologies at RAD Game tools, a company which essentially every gamer, expect maybe pure mobile gamers, has purchased a game that used their technology. It may be possible that he acts (or acted in HMH) based on outdated trivia and favoured premature unfounded optimization, but I find it hard to believe based on the content of his I've engaged with and his track record.
But you should no more follow Casey in form and function than you would any other fundamentalist.
The religious comparison is also a telling one given the state of the industry; for we aren't the theologian, we're the common folk looking for someone or something to follow in order to write better code.
Who are Casey's alternatives? Gesturing the cppcon as a learning resource has "read research papers to learn about a field" vibes. They can be highly informative and worth the effort, but not for beginners.
Who are Casey's contemporaries? If he's a fundamentalist then the atheists are nowhere to be seen by the beginners. Instead we have agile ceremony shamans, clean code bible missionaries, tdd doomsday cults, oop/rust/haskell/etc. zealots, a thriving megachurch industry of Lambda schools, and the mother of all cargo cults masquerading as web dev.
