I honestly cannot fathom why anyone working in the AI space would find $50 too much to spend to gain a deeper insight into the subject. Creating educational materials requires an insane amount of work, and I can promise, no matter how successful this book is, if rasbt were do the math on income generated over hours spent creating it wouldn't make sense as an hourly rate.

Plenty of other people have this understanding of these topics, and you know what they chose to do with that knowledge? Keep it to themselves and go work at OpenAI to make far more money keeping that knowledge private.

If you want to live in a world where this knowledge is open, at the very least refrain from publicly complaining about a book that cost roughly the same as a decent dinner.