David Rosenthal has been casting an unsentimental eye on industry trends for many years. One of his common themes is that most attempts to build decentralized systems fail.
His blog post goes through a many examples and shows that even without a technical driver of centralization, economic factors tend to drive towards centralization. It's depressing, but in the end facing reality is easier than the alternative.
DSHR's Blog - Decentralized Systems Aren't
Two counter-examples that he didn't talk about are email and RSS. It's interesting to me that some of the most vibrant areas of online culture, newsletters and podcasts, were enabled by these neglected, almost legacy technologies.