Good point, but there is a fulcrum point I think where too old has started to go down. There seems to be less demand for example for a lot of the sought after early SS machines, not a ton, but I recall a few years back many of those appeared more sought after than today.
I’m not sure if that will happen with the 90s, as this really was the most coveted age of machines, most of them filling the top 30, 40 and onward, with some new ones mixed in. If the same quality as wpc’s were continuously made since the fall of Williams, it would have happened, but since that as a whole has not happened, the 90s with likely be the standard all else is up against for many more years, and as such, prices will continue to rise for these machines as a whole, which is what we are seing.