If Rockbox is to be ok (except bootloader and drivers), the proposal should say "a program *that can be effectively run* on generally used computing hardware".
But I'm not sure that that's broad enough. It could leave a problem for video acceleration in drivers. I'd stick with looking for ways to ensure that mp3 players are wholly included in "generally used computing hardware".
The terrible decision about tablets does prove that legislators can make anti-citizen decisions, but the goal (enforce companies' DRM against computer users) shouldn't bind them to making bad decisions on patent questions.