You misunderstand. I'm not a a fan of all the pitchforks either, but this is the worst I've seen it. Whether you think those people are reasonable or not makes no difference - they're here. The best course of action is to try and understand why, and not repeat the same mistakes. And honestly, saying there's nothing the devs could have done better isn't true in my opinion - they did make a mistake.
No other developer has done a countdown that turned out to be just for a cinematic reveal for a product that may not release for up to 6 months later, and didn't provide a specific deadline date either.
Again, before you flame me, I'm not in the whining camp, I'm just trying to understand why people got annoyed - and I don't think simply telling them they're wrong is going to help.