I'm not seeing the sense in this approach. Whether T10 purposefully modeled the cars inaccurately or not because the licensing wasn't there would make no difference. You don't build a model to inaccuracy in hopes licensing is acquired & then leave it as such when it is, esp. not when the manufacturer is freely allowing you use of their other cars. The cars look the way they do because that was their standard at the time.They're probably gonna make a Festival Playlist out of this given the deleted cars.
Also, the reason why we're still getting these outdated assets like the 190E and the Countach is very simple. Sometimes, inaccurate modeling is done on purpose, because T10 didn't secure the license at the time, yet the cars were modeled anyway (usually via photo references) as filler and a Performance Index entry, according to someone on the forza.net forums. Copyright ownership is very much precise and very complex.
It might sound like nonsense but it's kinda what this is. That's the reason the Silvia S15, R32, Ferrari 575M and F355 look terrible because they were all designed in the FM2 era and those models were likely made before the license was acquired. You see this a lot with various games (ATS has a couple of new AI cars that look awkwardly modeled) and many create models not in a 1:1 representation of the car model.
Personally I'd prefer if those awful FM2 era cars were thrown out, despite the fact that many of them are 90s-2000s cars, and rebuilt.
The simple reason they haven't updated them is because they can't be bothered to source one of these vehicles & start with fresh data/reference material. I get that they have limited teams & are likely sending those teams out for new content, but the trade off of relying on older, outdated models becomes more apparent, esp. as they move from console to generation to console generation. These are X360 assets on a Series X they continually try to touch up, but their age is more than viewable.
ATS is a completely different situation where they're not looking to acquire any licensing to begin with outside the rigs, so keeping the AI models generic & faintly resembling real vehicles is their intended goal.