Some say a fast G4 with appropriate software is pretty unbeatable for music in OS9. Why not keep using it if it works, especially if they don't want internet video/ to do programming etc./ have the applications set up, paid for, and learned?

Mind you, the time will come when the kid wants Facebook and SIMS 17, which will only run on a 64-core fission reactor and in several terrabytes of RAM, and then they will cave. You watch.