High End is Dead?

Browsing used audio sites such as Audiogon and the Marts, high end gear ads are dominated by several dealers. Non-dealer ads are usually people trying to push 15+ year old off-brand junk at 60-70% of MSRP (when they were new). They don't sell anything. You could slash Wilsons, Magicos, etc, 50% off retail and no one will buy them.

No one buys if it costs more than 1k. It's not that they're not interested -- the ads get plenty of views. It's that the asking prices are just way over the ability of buyers to pay. Fact is, if you see a high end piece for sale it's probably by a dealer, often times trying to push it at 15% off retail because its a trade in, but also often they are taking a good chunk off the price 30, 40 sometimes 50% off. They can be famous brands with a million positive reviews. No buyers.

Are we just poor, and that's all there is to it? 
High-end system is not dead but its market share is much smaller.

How many people can afford a $50K+ system unless they are filthy rich?

Most of us only have a certain amount of disposable income.  A good audio system is only a dream.

I put together a system when I was in high school, Pioneer integrated amp, Dual 505-3 turntable, Nad turner, Nakamichi cassett deck, Denon CD player, and a pair of PSB book shelf speakers.  I had this system for the past 50 years (and I am still using it as my spare system) and it was only 2 years ago that I decided to buy myself a retirement present (audio system) because I do not have the same responsibilities as 50 years ago.
For many of us, the central thing that was happening in the 60's and 70's was the sudden surge in creativity of relevant music, and we wanted to experience it as fully as possible.  Our experiential lives were directly related to the music we experienced. It was our window into the world. HEA was a magical lens into the amazing musical events that were unfolding daily.  Now, the Internet and clever apps give us that lens into the world, so HEA has lost its value proposition.

In a world of batteries driving something as powerful as an iPhone, the big, heavy, dumb offerings of HEA seem dubious to greater numbers.

I don't know how I'd measure the health of HEA.  The number of dealers with real shops is way down in my experience.  The used market it much less vibrant than it used to be based on my awareness of sites that sell used HEA gear.  The number of people I personally know who have any interest in gear, over multiple decades, has always been either zero or one, so not much indication there.

HEA shows seem to be doing well.  The magazines seem healthy and relevant.  The amount of people designing and producing high-end gear seems to be as robust as ever.  

Unless one wants to define the specific criteria, I don't think you can say whether it's thriving, dying, or in-between.  It's definitely changing, but so is everything else.
My 24 year old son-in-law Just picked up some Elac B5's, and a lower level Project turntable. He had picked up 20-30 records getting ready. I wanted him to enjoy his 1st system so I donated a decent Rotel integrated amp, and he loves it. Sounds better than my system at his age.

I am waiting to make sure he listens and it doesn't just sit there, but I think I might have gotten another convert into this hobby.