Am I the only person who had a surprisingly positive experience with this feature? Yes, it took two attempts to work; the first time, I wasn't holding the phone close enough to the screen. But the ability to toggle between the two options allowed me to see which one I found to be preferable, and the color balance was much richer and more realistic.
I like the fact it calibrates the Apple TV and not my 8-year-old Samsung (I have an extensive 3D BluRay collection and will not move to a 4K monitor until it dies), and I went down a rabbit hole last night watching scenes from favorite films just to see how much better they looked.