Read almost all pages of this thread (have the yellow tint as well).
1. Apple is not going to be issuing a software update to correct the yellowing. If this is what’s keeping you from returning/getting another to try - do it now while you can still return - guarantee Apple will not issue software update for the yellowing.
2. Yellowing is largely due to two things, one being LG and the other the ability to pass off these differences as display variances (i.e. no issues). Have 2 OLED TVs from LG, one is perfect and the whites match that of Iphone X with the OLED “wow” factor, and the other TV has the yellowing exactly matching that of the Iphone 12.
3. Apple will likely release update to fix flashing/green coloring but again, guarantee nothing for yellowing - return now if the latter is what you are waiting for.
4. Too many issues overall with this release. Inability to focus (hardware issue, will not be corrected via software update), gaps in frames, slow/pixelated cameras, dull display colors, flashing, etc.
5. Yes, you can adjust for the yellowing from “color filters” and have it match/look even better than oem, but this is not a solution, the photos you take will not be accurate once transferred to another device and in general, things you see on your phone will not be in their true nature.
No one should have to accept these things regardless of amount paid, never mind that these iphones were touted as the best of the best. I guarantee you that anyone/everyone saying the screen is “fine” and slightly “warmer” has 1) never seen/had a good display and/or 2) is not comparing the phone next to on that has a good display and therefore cannot tell how it should be. You are paying for the most expensive, top of the line phone from the largest company (possibly 2nd largest company now) in the world - there is no excuse, return 100x if that’s what it takes for you to get one you’re satisfied with without these issues - as it should be.