We also have a 2018 X3 and the backup camera brightness is definitely brighter than the 2018 X2 during the daytime. People are saying the camera screen daytime brightness for the X2 is probably a default setting that I cannot change myself. That is unfortunate! Sunglasses, whether polarized or not, reduce brightness by at least a half an f stop. Most sunglasses reduce brightness by a full f stop. The screen in the X2 is much smaller than the X3. In order to see what is showing on the screen I have to take off my sunglasses and move my face over to within 18 inches of the camera - that is crazy! We live 75 miles from the dealer's service center, so I cannot just drop by to see if they can adjust the screen brightness.