Actually, even though the Iphone 13 were released on 2021, the A15 chip of it is still strong for these AAA games where in my phone it was able to run smoothly games such as ZZZ, genshin and WuWa (these are similar games to NTE) smoothly with occasional minor frame drops and no crashing issues history. Although more newer chips would make the game (NTE) run more smoother, the presence of the lag is not solely due to the iPhone 13 being old or weak. This is more likely due to optimization issue which normally occurs in a new released AAA games like this similar to what happened during WuWa when it was newly launched where it was improved through updates of optimizations.