Well, I've won diplomatically a lot of times (including Deity), but I never have used spies in city states or declared war on anyone. In a way my diplomacy victories were actually achieved by "true" diplomacy, that is staying friends with everyone (or at least trying to). So I don't think it's completely broken, just easily exploitable and because of that ironically achievable even if you're the biggest warmonger. Therefore I would like some changes to that, too, like the mentioned diplomacy with city-states even when at war.I agree that's what the devs decided. I do not agree that it is a good approach for a diplo VC. If they wanted to do this, they should have simply left it as an economic victory and ditched the diplo VC altogether. As it stands, they need to tweak the modifiers so that diplomacy really exists and works. Right now, it's all about war.
Not completely true, I had a game once where three out of five civilizations voted for me. The whole game I managed to stay at peace with everyone, and never bribed anyone to go to war. It certainly did feel at least a bit diplomatic.Diplomacy Victory can never be about "real" diplomacy, because it's a game and nobody will want to vote for you or help you win the game.