This happened to me as well yesterday. On a 15 Pro.
What did you end up doing? Full shut down / restart didn't fix it. I had a backup so I restored through iTunes. Touch screen is working again... so I guess it may not be a hardware issue, incredibly weird it persisted after reboots prior to the restore though. Never encountered anything like that before on past iPhones.
This happened to me as well yesterday. On a 15 Pro.
What did you end up doing? Full shut down / restart didn't fix it. I had a backup so I restored through iTunes. Touch screen is working again... so I guess it may not be a hardware issue, incredibly weird it persisted after reboots prior to the restore though. Never encountered anything like that before on past iPhones.