FIRST
The answer has nothing to do with the problem stated.
The Apple TV "APP" does NOT have that menu option.
It may be true for the Apple TV device though, I don't know.
SECOND
The problem has to do with auto-brightness during playback.
I could troubleshoot it by placing a light (my iPhone led light), close to the light sensor (at the top next to the camera) on my Macbook pro, with the light on the sensor, the movie became acceptable!
Without it, on a normal daylight setup, the movie is barely visible, like Trey mentioned is like staring to a pitch black hole that emits sound.
THIRD
I looked into System settings, Accessibility on System settings, the TV app settings.... there's NO WAY to control the brightness for yourself, we need to rely on that stupid sensor or watch a 2 hour movie holding a light next to the sensor or until your arm falls off.
LAST
Googling it, just gets you to the same replicated wrong solutions over and over.
Like no one cares what's the problem or even to understand it correctly.
It feels really bad to have a very expensive device with - supposedly - best display that you can't control a simple video brightness setup