This isn't a sequel to the first How People Learn book, it is more like a 300 page addendum or annotated lit review.
The first How People Learn book (1999) was written for a lay audience. You could recommend that book to anyone. How People Learn 2, however, is written in a traditional academic style, with little synthesis. Perhaps they did this consciously as a reaction against common over-simplifications of educational and psychological research, but it makes the text much less accessible and useful to practitioners.
There are major gaps in their coverage - online learning, for example, only merits a paragraph or two in this book, despite it being a major development over the past 20 years. There is little mention of evidence-based teaching techniques that have emerged in the past 20 years, either.
I'd recommend instead books like Teach Students How to Learn or Teach Yourself How to Learn by Saundra MacGuire or other related works, including the original How People Learn book.