I would guess that OP means that it is overly satured, and therefore that some color information is lost.
I noticed this sometimes happening for a few seconds when switching out from some apps that play video while having high brightness. I haven't had it occur permanently, though.
And I thought I was just imagining things. Then again I always had the feeling that the color profile slightly adjusted after major iOS releases. It always felt slightly off for a short time.
I saw some weirdness on my iPhone 7 Plus also. The green icon for the Nextdoor app seems different/brighter. I thought it was just me, but perhaps it's not.