I mean, definitely teenagers have always been dumb and driven by...uh, whatever term you want to use. And I agree -- if it wasn't Snapchat etc. there were other ways for dumb teenagers to be dumb teenagers.
But I just think the increased accessibility, ease of use, prevalence of tech and "anonymity" (until it isn't anymore) has made it more a concern than ever. I too grew up in the 56k AOL (or Prodigy or NetZero or whatever disc gave you X,000 hours of free internet!) days. I've just seen these changes, know some of the dumb and dangerous mistakes I made myself growing up, and realize they probably would have been amplified tenfold by what's out there today. I just really hope parents know and understand this, and can have honest discussions with their kids about it.