Augmented Reality Games heat Issue with iPhone X

Should apple repair or replace my device if it can’t handle AR games. Apple boasted about this new feature and compatibility with AR on iPhone 8 and X. Sadly. My iPhone X seems to warm up fast in just 3minutes through an AR Game. I have sent my phone on repair but as per apple technician, my phone was completely fine. No issues whatsoever. Then I tried again on 6 other AR Game apps, surprise surprise, still the same reaction. Warms in 3minutes in, builds up heat in 10-15mins. I have called apple support and someone from apple Australia called me up and helped me through this problem. Well, he said it’s the apps fault! Well then all 6 AR APPS?? I’m completely baffled on how quickly the blame shifts on the third party app when it’s clearly the phone’s incapability to handle high tech games is the real reason. Does anyone tried to play augmented reality games and experienced this issue? Please enlighten me. Should my phone be replaced?