2 Apple iPhone 13 Pro same model but different display quality

I bought two Iphone 13 Pro model, one from USA and other from India however the India phone always had a deep dark display with less brightness as compared to USA one. Apple support though says that both phones are identical however I see the difference and sent India device to service center Bangalore, India (Planet Care, VR Mall). They found camera problem and replaced however do not agree with Display quality. Phone is with them for 3 weeks and we are just taking to Apple Support which provide s hope for a solution however at end they say Service Center decision is final. The product was sent to ARC and now asked to escalate to engineering team.

The whole experience with false hopes from Apple technical support and customer care tells Apple themselves are biased in there products for different region as support says same model will have different display. Just see the photos attached - Red cover phone is from USA and other from India. To my surprise, Apple support and Planetcare service center in India said two phones of same model can have different display and yellowish tint. LOL however they dont want to give in writing. Can you guys help as we are Youtube Vloggers and camera quality is much needed for better content. Please help.