Twitch viewers of the games just to show how great D3 is.
Diablo 3 - 534
Diablo 2 - 254
Blizzard gave up on D3 years ago and you can continue to see how they don't care by the lack of D3's presence at any gaming event. (Blizzcon and Gamescon) Yeah, you are right that in D3 someone can play any class but how can that even be a thing to say? Every class should have been viable from the start. Might as well just play PoE and play a game that has variety and choices if you want to play a game like D3.