Movie does a disservice to the music
The Scatman song is great, but the movie does not do it justice. There's not enough things moving to it, and some bits felt like random animations with no relation to the song.
John Scatman was a guy who stuttered and decided to make music out of it. "Scat" is a jazz term in which the human voice are used as instrument playing sounds (beep boop etc). The song is about overcoming your hardships the same way the guy did (he was ashamed of his stuttering, but made a signing career out of it).