The trouble is, for anyone under about 70, more or less, the concept of photographic history is a bit distorted.
You can go to some schools, listen to all their old farts telling you about old processes etc. but they never tell you the truth that the ones without a dog in that fight can see. That truth is that photography was something that you learned via apprenticeship or hobby, and from looking at magazines and the very few photographic monographs that you came across. Instead, in recent decades it has become a new, teachable subject in art schools, as distinct from technical colleges where, for a brief period I had to attend, too.
That situation has created a handy niche within the educational establishment where lots of people can make an extra buck from talking about something instead of doing it. That incentive becomes self-perpetuating, there are grants available, and so you get people rabbiting on about images and tacking them onto the tails of other socially motivated ideas and psychological concepts that have nothing to do with photography other than provide playgrounds where anyone, with or without talent, can play and think himself a king; there are ever those other fellow players who will stand up and cheer, if for no other reason that they are swimming in it together.
You can, today, make an absolutely bland, featureless photograph, claim some silly absurdity of a genre for it, and hey, you're on your way. Think of that grim period of fashion photography that made a star of Corinne Day, that gave a platform to Nan Goldin et al. and you begin to get the picture: it's the art establishment that is responsible for this trend, because in my view, it is there to do one thing: make money for itself by building up stables of people that, in a sane world, would never sell anything. Where the age thing comes in, is memory: we/I or any similarly aged person well remembers a time when photographs depended on technique, content and purpose. For younger people this appears to have become an embarrassingly awkward thought, reactionary even, because if your diet is tweeting, texting and living your life in your palm, then no wonder anything goes if only because, in your world of dinner plate art, anything and everything does, indeed, go. Without expectations of excellence, you get no excellence, which is where we came in.
Just another old fart's opinion, of course.