Saddles do break down. Not only might you get less support in important places, but you may actually end up closer to the cranks. I have had to raise saddles as they aged to offset the collapse of padding and curvature that both occur. Usually only a couple mm, but still. IIWY, I would first check your "effective" saddle height against what you want it to be. If you fix that and still have comfort issues, it may be time for a replacement.