Civ isn’t really that complicated compared to sc — “real-time” play is a big burden, and dramatically increases the search space.

I think the bigger blocker is that civ has no real tournaments to fuel AI popularity, that the game (and 4X in general) is likely buggier due to less online-play (meaning the AI is likelier to get trapped exploiting uninteresting bugs) and at least newer games are probably somewhat unoptimized and will have longer simulation times (thus slower training) (both valve and blizzard are quite good about making games playable on a toaster; Firaxis is.... not.)

Sure, Civ has a lot of buttons to press and things to choose but is it much more complicated than StarCraft II? Never played SC2 but it sure seems there's a lot of buttons to press and things to choose.