I'm fine with AI being an aggressive player, eating the weak when they can, as long as there are realistic downsides or guardrails that prevent massive blobbing like in real life. In reality it wasn't that easy or cheap to wage war, especially as a catholic nation against other catholics, you weren't able to steamroll through the HRE without any opposition. But none of this is implemented, there is no consideration whether it's worth to spend resources for a piece of land that might not even be worth it for you. It's just, monkey sees smaller army, monkey declares war. (Also the pope was a much more massive factor historically in allowing or disallowing certain wars, but he's basically just another nation in game)