The Gearpocalypse won't be about Fender and Gibson and Marshall and Vox gear from 1948 to 1965. It'll be about high end guitars from builders only famous among gearheads, and the proliferation of Custom Shops (in all their variety). It'll crush the value of formerly bespoke pedals from obscure builders. It'll hit amps, especially big ones, that are high end but not Big Three. The really old stuff was made in much smaller numbers for a much smaller market back in the day. Those smaller numbers dwindle due to wear and butchering and simple mistakes. Those values won't collapse, because supply isn't sufficient for even half of current demand. But that Bogner Shiva or Soldano SLO, that 10 top quilt or R9 or CS Masterbuilt Tele is another story altogether.