Have you been able to fix this yet? The same exact thing happens to my XS max, it lags when swiping the page right after unlocking and it’s very annoying. I’ve already tried resetting all settings and erasing the device and setting up as new and nothing has worked. Don’t know if a restore in dfu mode via iTunes will work because a normal restore fixed the problem momentarily, but it started doing the same thing again even when setting up as a new phone. A reboot and hard rest also only fix the problem momentarily. I am on the official release of 12.3. Has anyone been able to fix this? Please help, Apple insists my device is fine and won’t replace it via warranty.