The thread has lost its focus on the original proposal, which is that IF class D becomes accepted by audiophiles there may be a glut of expensive "Big Iron" on the market at fire sale prices. Many have simply commented that that the IF will not happen because of quality differences between Class A, AB and D, real or perceived.
I would propose that the IF has actually begun to happen as more high end companies release their improved class D designs. I myself am entering into the research phase for new amplification for my 20 year old class massive class A/AB amplified 2 channel set up. One of the products I'm interested in is the BHK Signature 300 Monoblocs from PS Audio, a hybrid tube input/Mosfet output stage design of Bascom King. At $15k MSRP they are expensive, but far from outlandishly so compared to many other products out there. That is low end Pass and medium end ARC, for example. But Paul McGowan and his team are releasing a class D mono block that lists for 1/5th the price which naturally piques my curiosity. While I hope that the cheaper amps will not outperform or even remotely equal the sonics of their more expensive brethren, the question will most certainly be how musically satisfying are they for 1/5th the price. If the answer is anything north of 80%, or simply fine nuance differences, I would have to seriously think about it before pulling the trigger on the 300s. Obviously since I am even considering the 300s I can afford them, but that is certainly not the case for many audiophiles. $15k amps probably reside in $50k systems realistically. But in a $20k system, which probably represents a lot of audiophiles, $3k amps would allow more opportunity to upgrade speakers, or add a music server or analog rig, etc. This will be good for high end manufacturers and I hope to see the technology continue to improve.