Oh it's absolutely our fault. Do we care? Probably not. I don't at least. The only person whose beliefs I personally criticise is Sakurai's lol, because I feel that some of his choices for characters are whack yo. ...And that's why Shulk hasn't got me down. The chance of Gematsu being wrong is <1% at this rate. Got nothing against Shulk, I just sigh as the leak looks more and more true as time goes by which means more and more characters I'm not interested in (or in the case of Shulk, characters who I'm not familiar with) making it in.
So that brings me to my next point; should I be excited that another character with a (presumably) unique and interesting playstyle/moveset got in the game? Yes, yes I should. The only issue here is that I'd rather play as a character I want in the game (eg. Robin) who is also fun to play as, than someone who I don't care about who is fun to play as. I just wanted something that suits me better, that's all. I'll end up trying out Shulk, along with all of the other newcomers except the Chorus Men, don't you worry about that.
Am I being selfish? Maybe. But I don't think anyone (except maybe 3 people in the Amazon jungle) wanted the Chorus Men in before Gematsu said anything about it. Sakurai is doing what he does best, making himself laugh.
TL;DR - It's Sakurai's fault, not Shulk's or Sal's or the leaker's.