That’s your view, I suspect it is cultural. Humour in England can gain you a lot of respect but appreciate it is tricky to use globally and in written form. Regardless, at most he was being flippant. Not my fight so step out.
WRT the AI, it is not as such, it is a bunch of decision paths that already has shown time and again it is too simplistic.
If a civ has denounced you they will not deal so nicely with you and their ability to accept embassies or friend requests depends on how much they like you so you appear to be making a generalisation.
Yes things are not perfect but they have tried.
I totally agree. They have tried. But I'm not sure to agree with the reason they failed.
Friend request and some straigh forward factors deppend on if they like you or not. Probably cause you can perceive directly the agency of your actions, as a player this way.
The AI reacting in the exact same way if an friend attacks and enemy or an enemy attacks a friend, would be a behaviour very easy to change. It would Increase a lot the complexity of the game, and the approach to diplomacy. Why this has not been done? Precisely because of that.
AI behaviours may be simplistic, but they were introduced by someone with a consistent idea and design philosophy in mind. There are, flaws, and obvious mistakes. But I also see a clear motive in the way it was put together.
The AI is mostly deffensive. It is designed to deffend well from military aggression but also to rarely attack or be opportunistic. This is intentional, so the player is not attacked when in a weak position, or distracted in a different war.
The AI expands science, economy and religion in a steady non overwhelming fashion. Taking its time, being distracted. I think this is intentional, so the player can freely play without much pressure.
It very rarely uses big invasion forces for aggresion or after starting a war, it stops when taking one or two cities, that usually loses inmediately after because it didnt conquer enough territory to hold loyality. I think this is done intentionally, so the player can recover from a hit.
It does not declare surprise wars, or take entire civilizations, it does not betray friends, I dont think it rejects promises, or refuses to aid in emergencies. This is also intentional, so the player would not be frustrated due to the AI being unpredictable or stealing victories from the player.
As an AI researcher myself, to me this is not only intentional. It is consistent with the way war wearines, grievances, casus belli, and the warmonguer mechanics are implemented. The player can ignore emergencies, or decide to become a warmonger, but the AI cannot. The AI behabes like a good boy the player can have fun with.
The entire game is balanced that way. From disasters to dark ages to emergencies. Every system is designed to provide the player a canvas that is mostly decorative. And does not interfere too much, and can decide to ignore. No negative effects, no big drawbacks.
Only the first stages of the game can be frustrating. This is alsi intentional. A player that has invensted many hours in the game should win, to avoid frustration. The entire game is designed to make the game easier as advances. The same happened with the X-Com saga, and is a deliverate choice.