Powerful is a fairly short book (4 hours) which is a longer version of Culture Deck slides. The book is easy to read and very well structured.
Patty describes her work at Netflix as a head of HR. She explains why she made certain choices. Patty provides good reasoning and practical advice. I mostly agree with her points. Most companies, in my experience, are suffering from excessive positivity and family vibes which hurt productivity. Instead of firing underperformers, they are transferred to another team. I'm yet to see a company which has a culture of timely constructive feedback. That's some of the points that Patty touches on.
However it's important to remember the context surrounding her experience. Netflix is a public company which grew at a stunning rate. The challenges they faced are quite different from what any small or large company would. So her advice should be taken with caution.
I'd recommend this book to managers and higher (like cofounders and HR). Just like Nine Lies About Work book, it will help you question industry status quo and think of alternatives.