It's also this sort of work that's becoming less necessary with AI, for better or worse. This appears to be a crazy good guide, but I bet asking e.g. Claude to teach you about git (specific concepts or generate the whole guide outline and go wide on it) would be at least as good.
I also think if you are at the “don’t know what you don’t know” point of learning a topic it’s very hard to direct an AI to generate comprehensive learning material.
The main advantage of LLMs is that you can ask specific questions about things that confuse you, which makes iterating to a correct mental model much faster. It's like having your own personal tutor at your beck and call. Good guidebooks attempt to do this statically... anticipate questions and confusions at the right points, and it's a great skill to do this well. But it's still not the same as full interactivity.
When it’s just a book. I find myself having questions like you mentioned. When it’s just LLMs I feel like I don’t have any structure for my mind to hold on to.
I also feel like there is an art to picking the right order to approach learning a topic, which authors are better at than LLMs.
A good book by an expert is still better than LLMs at providing high-level priorities, a roadmap for new territory, and an introduction to the way practitioners think about their subject (though for many subjects LLMs are pretty good at this too). But the LLMs boost a book's effectiveness by being your individualized tutor.