Yeah it's almost always "faux K" and that's totally fine, the people who keep saying it's native just need to stop spreading misinformation. I also notice some screen tearing at the top from time to time.
Forza 7 is one of the rare true Native 4K 60FPS locked games on console. Gears 5 while does look nice, is not one of those and people need to stop spreading false information.