I noticed this earlier during my game as the Ottomans, but the AI really makes some dumb peace offers to me sometimes. Like during the second war Austria declared on me. They had a few small countries from Europe join them, but none of them really did anything. I sank a couple of their small fleets, and killed the 5,000 strong stack Austria managed to land on my territory. So if anything the war is going in my favor, yet for some reason the AI keeps sending me peace deals demanding I free my vassal of such and such country or pay them over half my money. Then a month or so later they offer me a white peace. I know the AI can be stupid but I don't remember them making such bad demands in my other recent games.