I wonder if the main problem isn't the generational handover of the hobbyist's collection and knowledge. It probably isn't that hard to find someone who'll geek out on old pinball machines, radios, Linotype machines, cars, big honkin' mills and lathes, partly because they remember them when they were younger so there was a strong impression made. Domain knowledge can be ferreted out from some still-living people.
I was thinking about that while watching this guy and his 11 buildings of stuff: