It's the whole retro thing and putting car back to original, or at least those times.
But I think a lot of it is also once something becomes hard to find, or intact and good condition, they become desireable to those who weren't as bothered before. Not only do they store them away, just in case (ahem) they also grab them when they show up to resell, and occasionally even use.
Also, window tint guys don't like the wrap around glass on these, I was advised by one years ago when chatting, to just put a rear louver on instead, easier said than done sometimes, even back then you couldn't simply go find one and ship around the world!
Yes, a 3rd Gen would make a difference, half the car is rear glass! They also look good with window tint. Some of the older classics, basically anything with chrome, can look odd at times, especially very dark tint, if the rest stock. My car already has the factory green tint glass, if I went further it would still be a minimum tint to add slightly more, but not noticeably more, maybe protect the glass from scratching for an extra year or two!