Yellowish Screen

I bought my iPhone 7 last September 2018 and when I had it side by side with an iPhone 6/6s, I’ve noticed that the screen of my iPhone looks a bit yellowish and dimmer and I thought it’s supposed to be better and brighter display than the predecessors. I’ve searched videos about it on YouTube and they also have the same issues but they said it should be fixed after few months (due to adhesives or chemicals used). But it’s been like 7 months and it’s still the same; the screen looks yellowish and bit dimmer. Is this really what the iPhone 7’s screen looks like? Or I might have purchased a copycat iPhone?