Upon further testing, we have concluded that at max volume, or near it, (we have a big living room) we DEFINITELY think that everything sounds louder and richer with BOTH reduce loud sounds and enhanced dialogue off.
A couple of examples that perhaps you could try: Search for the "Napoleon" trailer in the Apple TV app, and play the "trailer 2". The first scene of the trailer is DEFINITELY louder with "Enhanced Dialogue" off.
The Haunting of Hill House on Netflix, episode 1: The opening sequence narration is DEFINITELY louder with Enhanced Dialogue off.
At very low volumes though, Enhanced Dialogue makes voices clearer.
Very strange.
Anyone else with the same issue?