I think I have the 2014 version. I don't think the IBM story itself is too important, but it does make me a bit more skeptical about other things that I have little firsthand knowledge of. As a comparison I remember reading a local newspaper article about something I happened to be involved in and the details were a bit off, making me wonder about the other articles I had no prior knowledge of.
The Wizard of Oz bit is mostly color, but he relates it to the difficulty state-money theorists have had in coming up with similar narratives, and also that the myth of barter has persisted for lack of a similar anthropological myth for money.
I had forgotten about the Wizard of Oz bit! I don't recall if it was meant as an aside or it was meant to support a larger point about public opinion of bimetallism.
The bulk of the middle section of the book is mostly just meh. The final chapter though is something to behold! It's comically bad.
The book remains fairly popular in certain circles. If not for anything else, read it so you can politely refute the person who brings it up at a party.