I also have direct gameplay from this same track, if anything it looks even better since you can see sparks flying from other cars going down slopes, hard breaklights etc. In no realm does Forza look better, not even close and this is YT compression compared to the real 4K video.
EDIT: Here is the actual gameplay. Yes you dont have the cinematic shots but the level of detail, lighting, where night actually looks like night and you cant see shit, stars in the sky slowly dissapearing as the day transition happens, haze showing up at one lower end of the track which is the biggest dip in the whole course etc. These are things I havent experienced in Forza 8, it just felt like such a bland racer compared to GT.