Knock on wood, I've not been hacked yet either, though I've been around since open beta. This is despite the fact that I think two factor authentication (e.g. Authenticator) is simply a pain, I carry enough stuff in my pockets. I don't even have two factor on my bank account...
I'm glad someone has admitted to buying WoW gold... This still has to be stopped to reduce the hacking. I'm somewhat paranoid now as my account has enough gold attained by quests/drops/auction house to fund 30 epic fliers now(my 8 80s have epic flying already, too)... And thus would be a jackpot for a hacker looking for quick gold to sell to a gold buyer, dirty or not... (Blizzard made getting gold almost too easy IMHO yet people still buy??? I suppose just impatience...)
My bnet id is unique, and I run WoW in a slightly 1-off operating system (the 'unsupported' WoW OS), don't do questionable stuff on my WoW machine, and monitor suspicious activity carefully... Hope this is enough to not need two factor and still ward off hackers...