The only problem with this argument, in my humble opinion, is the analogy itself, as useful as it might be in some contexts. Personally, I love both highly resolving HP and speaker systems, but I do not think either one of them can ever satisfactorily replace the other, which means that, in the end, they are different "animals" altogether, so to speak. I have actually stopped trying to compare them (to the extent that I can avoid comparing them) because I like to regard hearing music from speakers, as an entirely different experience from the way I hear it from headphones, because to me, they are always entirely different.
The fact that headphone listening is so intimate, and excludes any acoustic involvement of the room in which the listening takes place, are the first two major differences that separate the experience, in my view, from speaker listening, which is always colored by variable conditions of room acoustics, and also, by the listening pleasure or displeasure of other people (I mean actually or potentially present other.listening parties).
This might not mean much to others, but when I am listening to a piece of music on speakers, and someone else is present in the room (or if I suspect other people might be hearing the music from nearby locations), I cannot help wondering whether the other parties are enjoying the music as much as I am, or whether they're hating it and feeling disturbed/annoyed by it.
Another way or putting this is to attend a live concert of one's favorite band or group with a live audience, and then compare that collective experience to listening to an excellent recording of the same live performance alone, in isolation, and on headphones. Assuming, for the sake of argument, that the recording will produce an exact replica of the music one heard at the concert with the live audience, I can almost guarantee 100%, that the headphone experience will be profoundly different, on the levels of both the sonic and emotional resonances that the same music might yield.
Ergo, headphone listening is always profoundly different from speaker listening : if the comparison of the two mediums is interesting (and I agree that it is interesting), it is precisely because of the difference, not in spite of it. Besides, I personally know of a few speaker-listening audiophiles who cannot stand headphones at all. However, I have never encountered the reverse group, namely, exclusive headphone listening audiophiles who cannot stand listening on speakers, but it wouldn't surprise me at all if such audiophiles exist as well.
Okay, I shall stop the rambling here. I am beginning to feel as if I have too much disposable time on my hands, which I really don't