Play as Inferno.

This person clearly meant that Wing is overpowered for demons.

Exactly ;) The topic is about Inferno.
It's not a problem to get artifacts for initiative at that stage. How do you defeat a Wing at level 30? He will have 3 artifacts for initiative, and he might even have one from the dragon set - that one also provides a good amount of initiative. I can't imagine how a good player could defeat Wing with Inferno at that stage. Staff of the Underworld + Cloak of Deathly Shadows + Stormwind (and even then, Light) - absolutely necessary!!! And play as Nibros... hmm. I don't see any other options. And even that isn't a very good option :(