I forgot I read this book since I read it in January, but you're absolutely right. It's hard to learn about large scale architectures since such scale isn't something every company gets to deal with. I like when a book teaches me a lot, but also makes me realize how much more there is that I don't know, and this book did that for sure.
I read it in preparation for an interview this year. A concise overview of scalability problems and their solutions.