Watch their interviews. They are plenty passionate about cars. Hell, watch the crew creative director interview. the guy lives, eats and shits cars and hes making his car games for ubisoft. Passion is not something that these guys are lacking. Talent, priorities, hardware, maybe, but hard to blame passion. the guys at the top wouldnt have taken 6 years to push this game out if they werent passionate. they wouldve continued making soulless cash grabs every two years. Phil and Turn10 leadership made the right decision to give this team time, but it didnt really pan out in all aspects. Still, the upgrade from the last game is substantial and there is no denying that.
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They built their tracks from the ground up, their driving physics from the ground up, foliage from ground up, implemented damage physics, weather, dynamic time of day, multiplayer penalty systems, lighting systems and ALL materials from the ground up. It is not your soulless yearly incremental upgrade.
The jump is there because the passion was there, but if you like GT7 more thats fine too. I never liked the Forza series either but credit where credit is due and they have put a lot of effort into rebooting the series.