Looking at old PowerBooks for sale on Yahoo! Auctions or Mercari, one thing you notice right away is that at times the majority of them have totally messed-up LCD panels. They're all bubbled up, crinkled or looked like they have huge scratches.
I attributed it to the high heat and humidity of Japanese summers, it doesn't seem far fetched that a laptop stored in an attic that reaches 40 C in summer will take some heavy damage.
I hadn't seen any discusson of this among western collectors, then I found a thread on the 68kmla forum that shows that the plague has also reached other parts of the world, perhaps to a lesser degree. More enterprising individuals there have peeled off the outer polarizing layer, revealing a pristine and working LCD, so maybe I should pick up one of the messed-up devices for dirt cheap and attempt a repair?
Here's a random selection of machines on auction when this was written exhibiting this behavior: