This seems to be the trend over the past couple of years. Started with Twitter with me, then Facebook, then Reddit. Hacker News, YouTube, and a couple mature news sites are about all I use outside of my own projects at this point. I've even gotten to the point, where I've installed comment section blockers in my browsers, so I won't see all of the horrible things people say to one another these days.
I'm honestly surprised on how much things like SnapChat, and even Facebook are still growing. It must be just the very young crowd, that hasn't gotten completely sick of it by now.