I am a casual player and play many types of games. I am very impressed by AI. I don't know if it improved much in the past decades but I'm not complaining. I'm not sure about other game types but the racing community is not happy with it.
But for IMO sim racing on Consoles ACC is far better than anything else.
You can actually race them, without them parking in the apex or push you into the wall everyother turn.
Also in ACC you can taylor the race. Its not like most of the games where you need to start from the back and overtake everyone in 3 laps and have to brute force your way through the field
All the other racing games I played on Console the AI is terrible.
If you want to see some interesting developments about AI in racing games you should take a look at twich from Stefano Casillo Kunos development.