that's the thing with digital cameras and PP... because one can see instant image reviews, people thinks its so easy, that they take their pictures and expect great results, and if not, they blame their cameras, digital technology being inferior to film, that there is some kind of esoteric techniques that will instantly make their images incredible that people selfishly refuse to tell them about, etc...
could it be that PP is the intervening factor... you know what happens when film is handed over to the developer, a technician who would adjust the film so that the images are optimised... or the people who developed film on their own, who would have to go through the chemical processess, mixing chemicals, timing the processing for control over the image...all that is PP...and in the digital age, PP is on the computer screen...its just that its very accessibility to everyone has made it look like cheating, as opposed to the impression that when film is given to developer, it somehow magically transforms itself into prints without the developers input...;p
PP has always been an important part in the past, it will still be important in the foreseeable future...oh and there is of course the very important skill of proper exposure...