I hate warm screens as well, but I'm surprised that its not widely known that this can be changed in the settings.
Go To:
Settings -> General -> Accessibility -> Display Accommodations -> Color Filters
Turn on "Color Filters"
Select "Color Tint"
Mess with the "Hue" slider until you get the desired look.
Here's a shot of my settings.
This is widely known, and also widely known it’s not a fix for those that have the issue, it’s a workaround at best. But TBH if that particular setting makes your screen look better, then you were very unlucky in the screen lottery.