Yes, but in the anarchic society, what stops men with guns from taking what they want?
You understand that you can still have anarchy without collectivism right? It's just called lawlessness, and when that happens, men with guns take what they want. Literally just look at any period of political instability in pretty much any country for just about all of history. What stops our current society from devolving into that if anarchic revolution were to occur?
Also, I'm not reading the book you linked. If there's relevant information, feel free to point out which paragraph/section.