The interview is clearly about a book; I assume they focused on the story around the writing of the book, rather than recapitulating the contents of the book. If you want to know what is done badly, and how to improve, I imagine the best thing would be to read the book.
https://www.nytimes.com/2016/12/28/books/language-at-the-spe...
quote: "Most of all, as he, teachers and other reading-instruction stakeholders have already joined forces to do in the Wisconsin Reading Coalition, he pleads with those who teach written communication and those who research it to start, at last, communicating with one another."
I have read many hundreds of interviews with non-fiction book authors, and they almost always include some of the specific ideas of the book. Indeed, usually that is most of what the interview is about.
