Not really. First, people love to write about the end of the world or in general about horrible end of something successfull. And second, Muller's video gave traction to this, for the lack of a better word, "movement" and now people are just jumping on that bandwagon of talking about how FB is a fraud or dying.
And it's not like this is the first post about future of FB. That stuff's been popping for a while now.