I hardly think of a room filled with furniture is considered a treated room. Certainly it offers acoustical benefits.
The title of the thread does not suggest the system would be placed inside an empty room. It merely suggests that good systems, or really good systems, may do an excellent job regardless of acoustical panels, or‘treatments’ placed about the room.
Reaching to a textbook to help figure out whether a situation sounds good or not may be helpful to some but I trust my ears to tell me what’s going on. I just feel people go nutty with acoustical treatments sometimes and somehow people are inclined to put a lot of acoustical panels all over the place. And gradually the room changes it may not always be for the better and people may not really recognize this. I’m tempted to remove the corner bass traps to see how things might change but that’s a pain to do, so for now I’m hopeful they benefit things. My curve for the subs seems perfect, I guess you could say this is a helpful confirmation but I really didn’t need to see it based on what I was hearing. I’ve learned to trust what I can hear. I still would like to find a nice diffuser panel but having trouble finding one I like, and I'm not sure how much it will really do.