I totally see iambateman's point, and agree with it. As far as inauthenticity goes, I would say that it pervades all aspects of our lives, including real-life interactions, which we can assume to be most authentic, yet at some level inauthentic (almost everyone changes themselves a bit depending on who they're talking to).

On this spectrum, the Snapchat experience is a lot more authentic and closer to real-life interactions than Instagram/Facebook, which are a lot worse multipliers of inauthenticity.