The Absurdity of it All

I'm 82 and soon to be 83. I can still hear a lightly struck triangle in the rear of the orchestra. Due to tons of amazing tweaks, my audio system is better than it has ever been. The resolution is such that I can discern between drum heads covered in animal skin vs those covered with acrylic. I no longer listen for detail, bass, etc., I just listen to a performance unfolding in front of me that expands into an amazing sound stage. The system is seamless. Each performer is defined in a three-dimensional space, with all instruments having a  lifelike size. I hear all of this with no problem. However, trying to carry a conversation in a crowded space, a restaurant, for example, affects my hearing. Ambient noise really sucks.

Frank

@oregonpapa 

Thank you for that. The difference between hearing, and listening.

Put an omni directional mic in a busy room. Play it back. Try do isolate any conversation and follow it. Not so easy to do. It hears everything, and listens to nothing.

However, if in the room, with visual cues and listening, its possible to filter through the noise. Although, I do find it quite difficult lately.

Put the same omni mic in the middle of the orchestra, and you're going to have a similar challenge isolating elements.

But, wether in that room with a live orchestra, or listening to the same properly recorded performance at home (key word is listening...) elements can be isolated with ease.

Listening is a skill, hearing is a matter of biology...

+1 oregonpapa

I think the OP has a point.
I work in a highish end retail store and am constantly asked by colleagues and customers what I think about how one item compares to another, whatever it may be.  I have to be honest...at 69 y/o, with many live rock concerts behing me, I am suffering from both age-related hearing loss and tinitus.  I still hear the sound of music through my diminished auditory instrument, and can compare reproduced sound to live sound as I hear it now, but I simply cannot discern what I once did.
Add to that the fact that my prime audiophile years were spent frequently under the influence of cannabis products, which I no longer do, and there is another factor distinguishing my "degree of certainty" about how things sound, relative to one another.  

It never ceases to puzzle me how combative so many who post to this site are. The OP, it seems to me, was making a simple point: the "improvements" supposedly attributable to different cables, cable risers, etc. etc., are extremely subtle if they exist at all; in general, they are not even measurable by devices far more sensitive that our ears. And "our" ears, for the most part, are no longer young; even if you've been careful, it's very unlikely you can hear anything above about 12 KHz if you're over 50. 

When I was in college, I made a practice of visiting the campus health center once a semester to have my ears properly cleaned. I'd spend the rest of that day listening to music: the improvement was startling, and thrilling. But it didn't last long. And now, of course, I could not restore my youthful hearing just by having my ears cleaned (I've tried). 

Yes, the ear/brain connection that delivers sounds to consciousness, where they become music, is complex, not very well understood, and arguably improves with age and experience. That's a truism, too. But it wasn't the OP's original point.

To perceive differences due to the electronic reproduction of frequencies that are too subtle even to be measured is problematic at any age, much less with age-compromised ears (and brains). So, sure: it all depends on what makes you happy, and no one, therefore, should make "objective" claims for tweaks or high-end products of almost any kind. BUT...this forum is all about offering advice to others about what to spend our money on. So things get out of hand easily; there's a strong confirmation bias involved in advocating for something one has decided is "worth" the investment.

I want to just say: Get over it! But that's beside the point, too, as it would seem to be advice incompatible with this entire forum.

So, at the end of this ramble, it seems I've answered my own original question. Why are audiophiles so defensive (and aggressive)? Because they've chosen, for whatever reasons, to spend a lot of money on things that cannot be shown to really make any objective difference, instead of on things their families need, or giving their "disposable income" to charities rather than to well-heeled audio hucksters. 

But, hey. Life's not fair. And "pleasure" is subjective and, as often as not, produced by webs of belief rather than objective facts.