I've never liked how some methods are used nowadays to cheapen production effort and time of animation, especially when used in combination with more traditional methods that exude love for the craft (depending on the artistic-style). It's very rare for something "mixed" to work, and requires vast understanding and experience not many have. In this case, it visually cheapens the movie as well.

That said, this story is nonsense, and not even worth discussing. It's just flat, boring and too weird for its own good. Even the Japanese songs feel forced and strange in parts. I'd stay far and away.