Honestly, I switched from a two year old Samsung to the iPhone 15, and it feels really disappointing and slow in comparison. The switch from 120hz back to 60 is really tuff, especially when your other devices are also 120 or 144. It just feels jittery and it would have been such a minimal cost for Apple to include it in this phone.
Honestly, reach out to Anker. When I had issues like this with an usb-c cable years ago they immediately sent me a replacement and did not even want the other one back.