I read this book as part of my Psychology of Aging course for my Fall 2020 semester. It wasn't particularly interesting to me, as most of the conclusions are that we can't make sweeping generalizations about people based on their age, because their individual circumstances cause for much diversity. One important thing to remember (which I already knew before dishing out hundreds of dollars for this course) is that what you believe about your age will be basically true. For instance, if you believe that you're losing your memory because you are getting older, you will perform worse on memory-related tasks than those who believe that they still have a strong memory, regardless of their age. In this way, believing is seeing.
The class was a breeze and I'm looking forward to the days when I can go back to learning about the things that really interest me, as opposed to learning basic concepts over a series of 3+ months. It's so unnecessarily dragged out.