Let me guess, you're an RPG'er in your heart?
That's the difference between RPG/Historical simulation/Empire building simulation or a hybrid of all and pure strategy.
I prefer to avoid labeling myself. Although the way I see it, games should be played for fun. We play games to relieve stress. When a game becomes so stressful that it stresses you out more than work or whatever, it's time to stop.
All I'm saying is I don't really agree that the AI is not trying to win. You can say they suck at it, but to say that they're not trying to win - no. For someone who is not trying to win, the AI wins
pretty often, especially at higher difficulties.
I'm also going to have to disagree with your statement that "numbercrunchers" are the only people who play to win and expect the AI to do the same. I don't consider myself a numbercruncher, and I play to win. I expect the AI to do the same, within reason.
The fact that the AIs are playing to win partly ruins the roleplaying experience because countries in real life are generally not playing to win by being the first to launch a spaceship, conquering the capital cities of all other major countries, or getting one of their citizens elected as UN Secretary-General. But it's fine with me.
To illustrate my point: Want to make an AI that
really tries to win? Make one that doesn't cooperate with the human player in any way. It will never trade with the human player, never form alliances with the human player, never interact with the human except to hinder his progress. This AI's interactions with the human player are essentially limited to denouncing him, declaring war on him, spying on him, converting his cities, etc. And that would get old very quickly, wouldn't it?