Earlier quoted context omitted.
It's not impoverished, it just has a different function. You could equally say "classical music is impoverished by its dismissal of danceability" (and you'd be equally wrong)
But there is lots of danceable classical music. My point is that mainstream music rigidly adheres to steady tempo and rhythm. If you only listen to mainstream music (like most people) then you don't hear much exploration of that entire 'dimension' of music.
I think that you and I have very different feelings about what is "danceable".
I don't have much time to listen to a lot of different types of music these days.