I reread Gogirls posts and didn't see anything condescending. She seems to be trying to understand the paradox of, if a four-figure system can be "high end" then, if so, why would you spend six-figures?
Part of it is the law of diminishing returns. A four-figure system will always contain compromises, at least IME. Forgetting headphones, where a 99th percentile system can be put together for under $10,000 pretty easily, most open air systems under $10,000 will not achieve deep bass. Music lovers a willing to make this sacrifice in order to really hear their texture of their favorite vocalist's instrument. This is a 90+% system, but it could be a 99% in it's imaging and presentation of midrange.
I wouldn't call that system mid-fi IF (this is a big IF)it does so with very minimal stress and electronic congestion in the presentation. OTOH, I've heard $50,000 systems that were full of electronic glare, congested midrange. A poor high-dollar system is usually only consider high-end by its owner.
Some of us grow old and find ourselves making lots and lots of money (it does happen) and find ourselves wanting to get rid of the compromises in our system, or at least most of them. (I don't know if there's a truly 100% system that EVERYONE would agree is the ultimate). I might could have done this a little sooner, but last year I moved from two-way mini-monitors to floor standing, almost-full-range speakers (roll off below 31Hz) and started upgrading the surrounding components.
My cables and ICs now cost more than my prior two-way systems speakers or amp. I'm chasing the final few percentiles of resolution and freedom from stress (hint, it's in the wires and sources mostly).
Is ego involved? Hell yes, but to widely varying degrees. For instance, my partner is building a four-million dollar house on the 8th hole of a famous golf course. Now there's an ego-statement, as much his wife's as his. Anyway, the sound system proposed by a consultant was MID SIX-FIGURES. I talked my partner out of it and he's spending high five-figures on security, lights and AV. Most importantly, he'll have a small, two-channel listening area. Several of his buddies spent the way more bucks, but their systems sound like pure crap. None of them know that, because none of them love music. It's a pure waste, based totally on ego.
The person with a more constrained budget still has ego. Many want to put together the best system possible for X-dollars. That's a man thing, mostly (my 21-year old daughter is an exception), but when you're constrained then you want to do the most with what you've got. This leads to debates, since there are so many choices that there's certainly no "best $5,000 system." I was part of this. I wanted to watch the jaws drop when my orchestral musician friends came over for a listen. I did that.
Now I struggle with how much to spend on others and how much to spend on myself. I've reached the point where a tithe is never a strain, so the question comes up as to whether I should give more. If I spend $10,000 on a CDP/SACDP wouldn't the money have been better spent helping typhon victims in Burma or tonado victims in the US??
Just so you know, I spent the $10,000 on my system, but comfortable with my ratio of self to others.
So, there are no absolutes. Must a high-end system be full-range, I think not, but it's not high-end in the same sense as the people that refining that last 1% of resolution, like AP. I think AP would agree, it's not the money, it's the result. IMHO, anyone with a truly musical system is in "high end". Of course, lots of people will disagree.
Dave