I used getabstract[0] in the past, where they give you a five page summary of the entire book. After reading a lot of them though, you start realizing a lot of business books are rather full of fluff.
I agree, there's a lot of fluff in business/productivity/self-improvement books. They're repetitive and often refer to the same decade old studies. I've also found that I need to be in the proper state of mind for a message to sink in. Maybe the regurgitation helps but I should reread a good book instead.
[0] https://www.getabstract.com/en/