Dynamic EQ is one of the features I like the most on the new Audyssey. It sounds great at low to medium volumes on both movies and music to me. Of course it flattens out the nearer you get to reference volume. What one person likes another may dislike, it's all the listeners preference. Someone else may like just Audyssey's filters without the EQ, or in bypass mode, or Audyssey disengaged and set up manually.
That makes sense to me. I'm always listening at about the same volume, which amounts to 5dB under reference. I rarely stray more than +/-3dB from that, so no need for DEQ. I still don't like the idea of processing the sound but I can see its value in a house where the volume needs to stay low at night.
When I remind myself of the broader needs people have, these features start to make sense. In the context of my own listening, it's not just personal preference—I've adapted my listening room and listening style to account for the shortcomings of not using room EQ. That said, lately I've been very impressed with what good headphones paired with a good DAC and amplifier can do for a mix, as opposed to any stereo.
I think it's instructive to listen to a good pair of cans in the same room as one's main system, to see how the music sounds with and without the room—in theory room correction should make a speaker-based system sound more like headphones. Ultimately that's one of the reasons I've gone the "no EQ except for bass" route.