I know Daniel, his work is not a ponzi scheme. Because you asked this question in good faith, I'll give you a summary in good faith:

1. The book you linked is just technical content. It teaches you how to use AWS, not how to sell books about using AWS.

2. Unlike the tongue-in-cheek examples of the original post based on minimal success, this book is written based on years of professional experience as a developer building AWS.

3. His content pops up pretty often because people like it.

Of course, if the book was part of a ponzi scheme, then part of that scheme would be having people like me defend it on HN :)