Dynamic doesn't necessarily mean "random". A game with dynamic music could still have a set of common themes. Good composers can blend themes together and make variations on a theme for any mood. There's no fundamental reason dynamic music couldn't be every bit as good, musically, as pre-composed music.
Proteus (video game) has procedural mixing of a pre-set score based on which objects the player is near at. I suppose not much in terms of actual composition (harmony etc), but something which continues to irk me (so to speak) to try to think whether more than that is feasibly doable presently (and not only in the future).
