Today my 1 month old 7 Plus camera was showing black screen preview all day. Then I force rebooted it with Power and Vol Down button combo.
To my relief, the camera started working normally.
Samsung has issued a mass recall for their battery problems because it's a legitimate safety issue, regardless of the number of units shipped. Not sure what kind of comparison you're trying to draw here.
And yeah, some bent their iPhone 6+. You know what? Some users didn't.
Everytime it's just a teeny tiny small percentage.