Starcraft II has thus far survived, and I have never seen a private WoW server in which all of the raid content works correctly (or indeed, even all of the raid content that's at least 2 years old).

What's important to Blizzard isn't that nobody ever breaks the security, but that they can delay that for long enough that people in the parts of the world that mostly pirated Warcraft III buy the game before anyone has working private servers.

The game itself will be made worse for everyone by this decision. Perhaps if it takes off as an esport we'll get to see BNet go down during tournaments like we have for SC2.

It's much easier for them to shut down 1 server vs. 20m pirated copies that need no server.