Gates has the right to do whatever he wants. As others have stated, he should have come out before the last election if he had a problem with the direction. Now, it is purely for profit as we cannot alter the path of the next three years. Waiting until after the 2nd term is not much different than releasing today. Maybe he felt like he could sell more books now than later since other books will also come out post-2016. If he has a problem with Hillary, maybe he wanted to affect public opinion now in hopes of impacting the next election. Seems like that was not his purpose, though, from the interviews out there.
In other words either way he was wrong, is that so?