Think it's just old. The first wave of overpowered jewelry was changed a few times. Original ones had no durability, and at some point the curses could stack. Later they added 255/255 durability to all jewels and made them only have a max of one curse. Someone correct me if I'm wrong, but didn't they also remove the 'unlucky' curse (stuff would have -100 luck) too, or does that still spawn on stuff?