I got the pro max. As I see it, true tone will make the image warmer than before. Just remind me of true tone on the 1st gen ipad pro. When turning it on, things got more yellow and I kept it off for a long time on it.
Also, I had a color calibrator before and when I calibrated a color accurate display (dell ultrasharp), things would get more yellow after the calibration.
I think the reason was because the whitepoint was set to be on the warmer side.
It is the same result on the pro max, things appear more yellow as the white point is on the warmer side. You can turn off true tone and it will be “back to normal” until maybe you put another device next to it, then it could still look like it has a tint.
I tested the black screen thing. The display has jo issue displaying black at full or min brightness.
I researched “black” on google, saved it as an image in photo, then I opened the image in picture app, and put it full screen. Once the gesture bar disappear, the phone looks like it is off and emit no light at all.
So from this, I conclude my display is working as it should.
Be sure you display a pure black image.