The most important thing to know is that this is not a book that looks at what the Bible has to say about men and masculinity. This is a book about the authors very specific idea of masculinity such that he makes a lot of assertions about his brand of masculinity and then vaguely hand waves at scripture, sometimes, if he remembers to. It’s completely backwards from the way we need to approach the Bible and understand God’s wisdom.
I don’t disagree with his more central elements of his criticism, but where he goes after posing this criticism is largely not to solutions but a fairly obvious collection of preferences of what are “real men” pulled from cherry picked behavior. Some of this is from historical men, not all of which are Christian, and some are just stereotypes broadly applied with very little consideration.
If you’re sort of vaguely angry about the way a lot of Christian men behave (maybe even how you behave) and you aren’t interested in reading the (whole) Bible and meditating on it to see what God has to tell us about masculinity, then I guess this could be a good wake-up call for you.
I will give the author credit that snuck in at the end between his insults of anything he views as remotely non-manly is the reminder that you must put into action what you learn. I didn’t learn anything from his book other than to stay away from this author, but this is a stance I take with the young adults I work with in my church.