This statement confuses me. I see how the fact that most people tend to cluster around a small number of platforms effectively at least trends this toward being more and more true, but what are the older "dark ages" referred to here? AOL? In the 90's you could take the easy route and sign up with AOL, but there were numerous dial-up ISPs you could choose from. Even then, you didn't have to use the AOL portal (though I'm sure non-tech savvy people who only used AOL for email never bothered to understand).