Earlier quoted context omitted.
A camera you carry all the time is worth more than one sitting at home.
Well, a camera that can't take the picture you want is as useless as the one sitting at home. And iPhone may be, in some cases, a camera that simply can't do what you want. It's a cellphone. Of course, you won't carry a DSLR camera with you all the time, and even that isn't enough, think about lenses, flash, tripod… but iPhone won't magically replace all that, when you actually need it.
Not so. It's a magical device, especially to those of us who remember the world prior to the beeper.