You keep saying this, but you're not saying how. How do you propose any game developer "evolve" cars racing on a track?
How? Is this a real question? First, you have the incorrect assumption that GT has "cars racing on track"
Racing is defined as being a competition. In GT single player, you are not in competition with the other cars on track. In Sport Mode, you are, but in single player, you are not.
I could literally write a book on the number of examples among driving games that have put decent game play into their single player over the past several decades.
And don't say "make the AI more than rolling chicanes," because the higher-level "chili" races in GT already demonstrate that they've done that.
Nope - The cars are faster, but they still don't race you, or each other. Even if I agree that it's good enough, it's a rare occurrence.
Unless you're delibertately being obtuse, and are trying to say that GT7's game play is no more advanced than that of Gran Prix, in which case you're just being stupid for stupidity's sake.
It is a demonstrably true statement. I even shared a video.
As supporting evidence, scroll through the myriad of "this AI is terrible" type posts from the last 2 decades on this forum.
Here, I'll even throw out just 1 example. Racing a Rival. Have 1 AI rival in the race that starts 1 position ahead of you. That Rival is going to try to win the race, or at the very least, try to maintain a lead over you. Your job is just to beat the rival, with the finishing position requirement being higher every time you run the race.
Here's a bonus. Remove the rubber banding and replace it with AI personalities. They have this tech from GT5's B spec.
As I said, I could write a book on all the achievable possibilities that they are simply not bothering to implement.