It doesn't matter what he called them. I couldn't care less. But the fact that a company like Blizzard does endorse it is the issue here. When You make a game that is so aimed towards casual fun, when You have very strict policies for harassment and offensive behaviour for both in game chats and forums, when You do it for a game that has a rating of 12+ You simply cannot allow Yourself for such mishaps.
It's pure lack of responsibility of someone on Blizzard side, and while people most likely did overact on the forums, it's better than just staying quiet.
Personally, why none of the insult over internet really get to me, because well... Why should they? I still try to understand why gamers so much like to use that type of insults so much? Why everything always is either "gay" or someone is a "fag" or "i hope you die"?
That's the image of gamers that does get outside, that's why gaming is considered as violence inducing, and that's why we can't have good things. Ever.
Minimal respect for the fact that there is a real person on the other end of the internet would go long way in making everyone's lives a little easier.