We have certainly seen some ultra-high-end audio manufacturers struggle a good bit, but there are also just as many mid-fi manufacturers that have struggled or closed as well.
It's true that in many cases the cost of ultra-high-end products has gone crazy, but there are a goodly number of ultra-high-end (and expensive) products that are actually a value for the money. Most people don't equate value with something that sells for $500K, but when you know what goes into some of these high-priced products you'll be amazed at the list of billable materials, not to mention the [very expensive] machinery that is necessary to build them. And yes, on the other side of the argument, there are many products that can't justify their crazy high prices.
Having said that, the ultra-high-end as a whole is doing quite well (most notably with sonically amazing and groundbreaking products). In the lower high-end to mid-fi category of products, the same principle holds true - some are a rip-off, and some are truly worth it, regardless of their price. So, to say that the ultra-high-end is dying, NO, I don't buy it. And I work in the middle of it.