Believe it or not, the book is actually a veiled criticism of the gold standard in late 19th century America. The author L. Frank Baum was on the side of bimetallism because he believed farmers were being forced into debt by banks due to a tighter money supply.
It’s actually fascinating stuff that I didn’t have any understanding of until after I learned about bitcoin.
Also, it’s worth reading the book because the movie is deeply flawed and changed too many of the concepts to even make sense when compared to the author’s original vision.