$23,000 is still a pretty penny.

I have for example this NXP1000, with twice the RAM:

ftp://ftp.ai.sri.com/pub/mailing-lists/slug/930331/msg00117.html

$18,700 in 1992. The last hardware Lisp Machine type.

Many years later I got mine for free from a telco equipment manufacturer.

I don't see the relevance. I, too, can easily find dead-end hardware that was expensive years ago that no one wants today. Most are just happy someone is taking that crap out of their hands. It's big, heavy, has strange power requirements, people forgot how to even turn it on and get it running, etc.