I have no idea. Your just going to have to take my word for it… or not.
Previous to the X I had a 7 and previous to that I had the 6 and so on. 6 was fine comapare to my previous 5s out of the box. Of course they are now extremely blue compared to the 7 and X.
When I got the 7 it was very noticeably yellow compared to the 6. I adjusted display accomodation to my liking. Then after a week, I noticed that my 7 was very blue. I turned of the adjustments and never looked back. The display was great.
Then I got my X. Of course it was very yellow looking compared to my 7, which now looks very blue. Again I adjusted display accomodation on the X. I had no other issues with it , so that was great.
Now a month later I noticed that the X was very blue. Turned of the adjustment. Display looks great now.
Of course it’s warmer that the previous iPhones but it’s not yellow. An overly blue display, to me looks like it has a haze over it.
That’s my experience. You can believe me, or you can dismiss it. Entirely up to you.
All I would say is, if all that you perceive wrong with your display, is yellow, and everything else is fine. I wouldn’t go changing the phone.