The book is like 5 years old... So, why now? Because of Twitter drama?
Edit: Well, it seems that, according to Wikipedia, the impetus might have been an article in tech media (which seems to mean anti-tech media these days).
He also was hired at Apple in April. ~2k Apple employees then signed a letter condemning his hiring after excerpts of his book circulated. This wasn't so much a Twitter mob resurfacing an old book, as a group of Apple employees using a published work to criticize the hiring of a new manager.
Edit: Well, it seems that, according to Wikipedia, the impetus might have been an article in tech media (which seems to mean anti-tech media these days).