Plus it just makes a hell of a lot more sense for a portable device to use internal memory for low res video.
UMD movie distribution was just a bad idea period that only became exemplified as soon as iPods with video functions were introduced.
Even as a form of game distribution, it was pretty far from being ideal as it is generally a bad idea for a low power portable device to use spinning optical media (power consumption, access times, additional moving parts, etc.). Plus the basic idea of carrying media for a portable device is essentially obsolete.







