It's not "bad" but it's not "good" in terms of graphics/animation, but as many people are saying: this movie uses movie clips. In my opinion, movie clips are (more or less) layers. In fact, one could create a movie clip the size of the flash file on only one layer, then create multiple layers in that movie clip and claim that everything was created in only a single layer of animation. Is that to say that this is inherently bad? No, not at all. It's okay. The music is very nice, for example, as many people pointed out. And as I also said, there's nothing wrong with the animation, it's just not wonderful.
Though, I also have to agree: even if this was done in one layer (which I do not believe it is), why does that actually... y'know... matter? It doesn't really prove anything, and I don't think it really shows off skills so much as it shows a more tedious way to create flahses. I mean, it is sort of admirable, but still.