If reports are correct, Buffett read the book before publication. It stands to reason that whatever has changed, and change need not be only for disharmonious reasons, is a result of something secondary to the contents of the book.
We all have opinions. I'm of the opinion that Alice was a bit over the top in promotions afterwards. That she was talking a bit as if she was Buffett. This would be fine if her comments were accurate with Buffett's true thoughts. She went off the reservation a little bit and would only seem logical not to further advocate for that.
A good example of her most recent rants is that of Buffett never advocating for dollar cost averaging. Fact is, he has recommended people do that. As an aside and what's interesting, he has been selective of when he does advocate for it. If I'm correct, he wasn't as forceful in his comments when markets where on a tear, but becomes more talkative about it when markets have been declining. Either way, he has suggested the average person should dollar cost average into a broad based index fund, and Alice has said he never has. There are more examples like this that has been coming out of her mouth over the past few months that at some point I think Warren says, "no mas."
Or, he just decided to move on. Simple as that. I don't think it has to do with the contents of the book.
Yours
Jack River