My XS Max looks completely fine to me. The color accuracy is great and there is no major blue shift (little compared to my previous X), even with true tone on. Color shift is there, however it isn't as blatant compared to my X. I professionally calibrate all of my displays at home for video and photo editing. I can say with confidence that my Max is well within the acceptable accuracy range and warmth levels.
With that being said, yes the phone is indeed warmer than the X and considerably more warmer than any iPhone below the 8 series w/o true tone and the OLED panel. This isn't necessarily a bad thing. It seems like a lot of iPhone users aren't used to color accurate and/or warm screens in general. The screen will stabilize over time and you will get used to it or you wont. That's the "con" so to speak of OLED displays.
Welcome to bleeding edge technology.
I compared my XS Max to the Note 9, S9+ and Google Pixel and Pixel XL at Best Buy. The Note 9 and S9+ have the same yellow-ish tint as the XS Max, although they were not as yellow. The Google Pixel and Pixel XL screens looked bad compared to the rest. Due to my experience, I am very comfortable and happy with my XS Max with true tone on. I'll be keeping this one for a while.