I know I must be late to the party. But for your information, and anyone will have the issue. Here is my experience with ipad mini5 display issues.
1st ipad mini I bought direct from apple is gray. It had that annoying pinkish blue tune to black color. And the display seemed not being fully laminated. And it also seemed they forgot to coat it with finger print resistance oil.
So, I bought a silver one from local store just to try my luck. The result is I now sit with a better ipad mini5. Even before I turn the display on, I knew it had a display from a different manufacturer. The display is fully laminated and stay dark black under strong light condition. And it is quite resistance to finger prints. Although I admit the view angle can still improve a little bit, however I am now happy with its much dark black.
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