I literally owned a phone for like 4 years that I just so happened to find on the side of the highway, laying out in direct sunlight. Every single image the camera ever took had a black spot in the middle of the upper left quadrant of the image, which covered somewhere around 20 or so pixels.

Every. Single. Image. The camera's sensor was damaged by the focused sunlight. Even if the photos hadn't been tagged by the phone's camera software, that damaged spot in the images could be used as something of a camera fingerprint.

Also, I've already made a point to emphasize this, I didn't say you can't briefly point it at the sun, I said don't leave it in the sun.

BTW, that phone ended up dying due to overheating, and it wasn't even in the sun, it was just a really hot day and I was using the phone while also charging it. If a phone can die like that, I'm pretty sure that ought to be another clue that you shouldn't leave your electronics out in the sunlight.