I'll say no, since he's one of the most over wrestlers right now. The fans at arenas seem to always enjoy when he comes out and appears, so it's been successful due to his constant and strong push over the past twelve months.
Now, as a fan myself, I find him to be stale right now, and I've considered him stale for about 8 months now. I enjoyed Punk until a little bit after the Triple H fued. Somewhere between that and the "super booking" where he was winning basically handicap matches against Del Rio and Miz, I stopped enjoying him. It was sort of a reality check that he was just being booked as another Cena with different dialouge. Though, he was growing stale to me even before that.
In terms of PPV sales, they don't seem to be blowing the doors off sales records when the main story revolves around Punk. But it's easy for apologists to pawn that off as "lazy booking" or "lackluster surrounding fueds". Even if that isn't the case (there's always lazy booking and lackluster fueds).
But yeah, basically, it depends on your view of "failed".
Punk is popular, and very over right now. So he's a success in that sense.
In terms of, "could he carry the show if Cena was completely gone", the answer is no. But to be fair, what current guy even could? It's not a fair comparison.
Still, I think considering how long and hard Punk's push has been there should be a lot more to show for it. So I am disappointed. . .but again, I definitely wouldn't say he's a failed project.