This is a fairly academic look at taking notes and what a personal knowledge graph is. The format of the book is a series of essays, that at times are helpful, but also spend entire chapters on defunct operating systems like Haiku. Yes Haiku runs still, but you’re never going to use it so telling us how awesome it is at making relationships between files is wasted time. Very few people are going to ever run Haiku no matter how good it may be for making note connections.
Unless you have a specific academic interest in PKM, this is a book to skip.