Like Millercarbon said, old things tend to go up in value due to rarity and collectability in our throw it out if it's broken society.
Technologies that get perfected incrementally are what you want. Just like 911s get a little better all the time, their owners have their preferences, whether they are air cooled, turbocharged, sunroof, cabriolet (convertible for the non-car folks). Regas (especially their arms) get better all the time, for 40 + years.
When technologies disappear from new production like an idler drive, there is a reason for that. I guess some people want to pay $23,000 for a turntable worth $2K just like some people will pay $900K for a new build of an old 911. They want that nostalgic look that is in style.
True audiophiles don't care how things look, only about the sound. Having it look nice is a plus, but IMHO it should not be part of the equation unless all else is equal.
Finally to answer the OP question, when I first started with audio equipment in college in the early 80's, all you heard about was that the Linn Sondek LP-12 was the ultimate turntable. Now there are so many good ones, it's hard to say what it most hyped. Also, the prices of some have gotten so stratospheric that they have become status symbols. VPI told me that some of their customers told them that one of their high end tables was too inexpensive. He thought it should cost $40K instead of $20K. I kid you not. They were from Asia somewhere and were trying to impress their friends.
