Well said. This was basically my second line of thought, but I hadn't shaped it into proper words yet. The content of this book seems useful, but perhaps it was simply too dense to use for a book club. I would be reluctant to suggest rules for content of books, or even rules for density.

One change that I’d make for future books, if it could be done, would be if the person that recommended the book would take lead on the discussion,

I support this measure. It could take care of some things. No offense to the OP who started things, but I think a sort of rotating leadership makes more sense for a book club. Assuming any other participant is actually interested in the responsibility.