@ALB123 i am with you wanting a better AI, in AC and any other SIM I drive. I have heard also that a majority of SIM driver in AC are mostly driving offline and occasionally go online. I believe this is also true for most SIM.
AI is often critiqued but when compared to racing online AI bring a satisfying experience more consistently, which is why it is favoured by most. Active people on Forum bring a distorted view as they also majoritarely are active online. I just find that too often AI gets a one way story which does not represent their real contribution to our driving pleasure.
Better (read complex/some level of awareness/behavioural character) AI is difficult, since any degree of unpredictability means a mounting of possible errors and interaction issues to address. And complex behaviour trees for such a "live" environment is computationally expensive.
The principal design point for AI is to not get in the way of the user. In many
ways.
AI has to be predictable to a degree, otherwise it frustrates the user since there's no pattern finding to overcome. AI has to be mindful of the users goal/purpose, othewise it frustrates the user since they'll most likely not reach them with a good AI (see all those chess computers).
To top that, when designing the "game rules", you have to consider that the majority of users play in 15 minutes to 40 minutes stints. 3 to 10 laps in every single game rings a bell.
That is why the majority of racing games take the well-trodden path: Paths. Cars fall in line with their racing lines. They can set varying paces and add a few "simple" rules on how to behave around the user/other objects that fit in their rules and game time frames easily.
The majority of the behaviour quirks noticed in this page can be taken to any other racing games, because that is mostly by design.
All that is to satisfy what you said: "AI brings a satisfying experience more consistently". And even then, it's a hard task because "good AI" has to cast a wide net.
Some see AIs that ram and fight for their spot on the track as good. Some don't.
Some see AIs that just set lap records one after the other as good. Some don't.
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With that I think it's easy to understand why multiplayer is understood as the natural endpoint for AI (caveat being a good connection/server).
Once everything (all those stats) is "triaged", you'll see you'll fall into a group of like-minded, behavioured people, that will likely have a similar pace as you.
And it does work consistently as well. That's why games like Overwatch, Rocket League, LoL and so on are huge. Or any organized sports. Racing included.
My only other AI experience is Gran Turismo 6 and we all know how awesome that AI was.
Thankfully, the AI in AC doesn't act anything like they do in GT6.
I agree, thankfully the AI in GT6 doesn't act too much like the AI in AC.
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On that note I don't think AC's AI is bad. It's functional. But as of now I don't see room or will for improvement, other than addressing some issues like their decision making in corners when grouped up.