As of July 2016, the top five websites in the United States are Google, Facebook, YouTube, Amazon, and Yahoo (according to Alexa). Odds are, five years from now this list will look pretty much the same. That’s because there is a network effect that makes it nearly impossible to draw users away from the top sites.
Google isn’t going anywhere. Facebook is also here to stay. The only real way to stop a website is before it becomes super popular. Just look at Yahoo and AOL. They won’t die.
Once a company dominates its category, it will dominate for the foreseeable future. Only a highly disruptive company can eventually unseat it. But you can see disruptive companies coming from a mile away. It was not a surprise when digital photography unseated Kodak as the leader in photography. They saw it coming for years, but wouldn’t do anything about it. The same thing was true when Google rose up and unseated Yahoo from the top spot on the Internet.
So we should think twice before believing that Google or Facebook might not be around in a few years. They will probably still be around in 20 years, just maybe not at the top.