I'm one of the book's two authors (the other is the head of Blink Rendering!) and I've talked to a number of people on the Chrome team. None of them have struck me as trying to keep browsers mysterious! On the contrary, folks who work on Chrome, Firefox, Safari, and Ladybird all seem incredibly excited to talk browsers and discuss how they work. The world of browser development is surprisingly small, the engineers often move between companies, and I think it'd be tough to keep a "conspiracy" going.

But I do think there's a real lack of teaching material (why I wrote the book) and even "common vocabulary" to discuss browser internals, especially for the core phases like layout and raster, which is something Chris and I are hoping to create with the book.