so you wish to change the definition of fidelity itself just so that more people can include themselves in the pretending game of high fidelity? the degree of fidelity is measured against a reference, that reference once picked(and it has to be picked) is unique. so just like a fact, whatever we call the alternatives, they remain something else. not a fact, not fidelity.
what you have going for you is that almost nobody aims at an achievable and known reference. so with that messed up, what follows doesn't really matter, at least not for fidelity. and with headphones it wouldn't be too far off to say that everybody is significantly wrong. most albums were panned for speakers(oops wrong stereo, talk about a "detail"). most people don't know what the music really sounded like originally(whatever they defined as original) and instead make up on the spot what they think it did sound like(AKA taste/preconception instead of fidelity). almost nobody knows what compensation to apply for his/her own ears for the missing body and head influences on sound.
so once we've established how far away most hifi people are from actual fidelity, your desire to include a given group to the merry band doesn't seem that problematic anymore ^_^. I say go for it.
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