Can't believe seven replies and each one is stupider than the last, Gaunt, Tonka, Ferocitus, you guys are on a roll keep it up.
I remember reading a similar thread about Stellaris, another 4X game like Civilization. This was around the time that Google computer bet the world champion at some game I can't remember the name of, and the it was like, why is '4X AI so bad?' Especially considering AI today compared to the 1990's, it seems like nothing has changed.
The Stellaris AI developer replied and explained that a game like Steallaris or Civilization is simply far too complex for any AI method we have today to process. AI seems to generally operate on a tree method, where every possible choice creates a fork and the computer processes inputs to determine which fork is best. In a 4X game there are simply too many states that the game can be in for a computer to process everything and then come up with the appropriate answer.
If you think about Chess vs. Civilization, Civilization is tremendously more complex. Every possible choice is a new fork in that tree that a computer AI uses to choose what to do. In Civilization, every possible choice by every player will create a new possibility to be followed up on. Then this needs to followed through for the entire game, so you end up with something much much higher than even trillion*trillion, I imagine.
The examples you cited, parking a car, Alexa,Siri are solving simpler problems, and are quite frankly, faking their AI imo. It's not difficult to confuse Siri, and Tesla cars will happy drive you into the side of truck. Don't believe the hype, 'AI' is a long way off.
Furthermore Civ 6 'fakes' their intelligence by adding character traits which simplify the AI in a meaningful way to the player.
It is amazing that every iteration of these games the AI is the same. This is simply an area of technology that has not developed in the slightest.