"Musical" is something in the head and understanding of the listener. A musical experience requires an understanding of music. Gear doesn't do it; someone can have a musical experience with subpar equipment if they're paying attention. There's nothing high fidelity about Enrico Caruso's acoustic recordings but there's a whole lot that's musical.
I used to challenge audiophiles re: historical recordings, specially classical. If you read audiophile forums you will see a lot of "the music is what really matters, we are all about the music in the end". Yet the amount of replies re: people not being able not getting over primitive sound was the majority. If you are missing (and like classical) Weintgartner's Beethoven because of sound, you are not "all about the music" in the end. IMHO, of course.
Musicality - hard to define when talking about music and musicians. Audio devices? pls.
My go-to analogy - medical devices. You see, we use this audio devices to reproduce mostly music. So believers of subjective analysis of this devices, came up with this to add some gravitas to their opinion.
Obviously it doesn't make sense. In the practice of medicine, empathy is good, right? But it would be extremely silly to say that a pulse-ox, a respirator, etc have empathy. Nice to have in the practice of medicine? Sure. Applies to medical devices? Obviously NOT.
My go-to scenario. Let's say you are designing an audio device. Now, if your boss is a believer, imagine they come with the order "THE DEVICE IS NOT MUSICAL ENOUGH, MAKE IT MORE MUSICAL!!!"
How much more musical? 20% more musical? 1.2234234% more musical? how do you measure you achieved it?
If I was in that impossible situation and wanted to keep my job, I would just guess what the evaluation group might like and just do that in the hopes of making them happy. Introduce some distortion, introduce some kind of an EQ curve. Maybe I could fool them. It still won't be musicality.
I know I am repeating myself - have posted this before - happy to see the concept actually being discussed.