I'm chiming in here as well, I noticed my iPhone 12 pro max is also warmer, but I'm comparing it to an iPad Air 2, which is several generations old. Since I traded in my 7 plus to get money off the new 12 pro max, I no longer have that to compare with. However, I do have experience and training in television, so I am used to cinema calibrations being much warmer, and in turn colors do look more natural under the warmer tint. The piece of information I lack is this being my first OLED display vs LCD. NOW, I did used to have a Plasma TV, which would be closer to OLED technology vs LCD because both generate their own light vs a backlight. I think what I might do is download an image of the white boot screen to the phone with the black apple since the new phones no longer have it, and look at the tint that way.
With all things considered, the display doesn't look distorted in any way, as in wrong colors, etc, and in dark mode things look fine. It's more as I said, not having experience with OLED until now, to know what they are supposed to look like. I did turn off true tone, that really makes it yellow, to the point it's not natural. It's almost like nightshift.
By the way for those comparing blueish tint to warm, especially when talking LCD: I think part of that is because of the LED backlighting that makes an LCD have that harsher tone at times because of the color of the LEDs vs a display such as CRT, Plasma, and OLED that generate their own light per pixel.