I bet if you could turn your DS into a music/movie player you would say how cool that was.
Oh wait, you do. The R4DS is like, the coolest thing ever. Who wouldve thought you could have a handheld that plays games, music and movies. Lets not forget the somehow popular cartoon shows on GBA carts. Low, choppy quality shows that were big sellers. Who wants NES Metriod for free when you can pay 20 bucks for it on the GBA.
But your right, no one needs a handheld that plays music/movies/emulators/games all out of the box. Just get a DS and spend the same amount, if not more, making your DS do half the things a PSP can.