Nah. The AI races are the same as they ever were—it was the surrounding CaRPG stuff that made the pre-PS3 games so much fun in single player. Taking a shitty Civic, changing parts and then finally adding a racing body kit was where it was at. It was never the on-track racing.
It was the same before and it is same now. Take some N200 car in "Professional League" cup and Midship Challenge race, bump or reduce strength or weight, choose different tyres, setup suspension, drivetrain, transmission and so on. It was the same in older GTs.