and ramble well you did.

My thoughts of possibly why many systems that use less than demanding music as you would like to listen to at audio shows do.

One reason may be due to a usual display room at such audio shows being a hotel room with physical defficiencies for music reproduction.
I know in the case at RMAF, the walls are typical sheet rock where low frequencies easily pass through to other rooms interfering with their demonstration.

Also, audio shows are not always the best place to hear the ability of a system to play as intended, optimum conditions.
RMAF has grown beyond their electrical system to be able to handle so many systems being displayed where Voltage sag can cause poor transients and dynamics, as a case in point.

Some other reasons may be due to prefered musical types based on the age group of the typical attendee at such shows, middle age like me.

And the one reason that I feel is more prominant than most, is that there system could show to many of its short comings playing extremely challenging music types, like rock and heavy classical with some extreme dynamic swings.

I am sure that you know from your experience that there is no speaker that does it all.

Hard core audio fans usually have more than one system in order to play all of their prefered music well.
Maybe a panal dipolar type speaker like a Quad 57 would sound great with vocals and easy listening music.
A more conventional cone speaker might play a little more types of music well, like pop and middle of the road.
And then, you have high efficiency horn speakers for the clasical and rock clashes and heavy transients, wham bam thank you maam.

I like the sound of Duke's Dream Maker speakers too, a little of both worlds, dipolar and high efficiency with dynamaics rolled into one.
I feel the Dream Maker bipolar speakers are one of the most balanced sounding across the full frequency spectrum as most that I have heard in my experience.

But that is my opinion based on my taste. Music taste is subjective and personal.

YMMV

Have fun!

Norris