The publisher absolutely has the right to not publish the book. It's also very possible the author is being a bit unreasonable and bitter. We are only getting

The publisher absolutely has the right to not publish the book. It's also very possible the author is being a bit unreasonable and bitter. We are only getting one side of the story. However, I read this more as a warning that there is a bias in the publishing world and to not look at currently-published works in the aggregate as an unbiased body of work.