Distributed, not decentralized
History of the Internet has shown that decentralized was never enough. E-Mail is an excellent example. It's federated architecture enabled Hotmail (Microsoft) and later Google Mail to become its largest nodes, concentrating all the users that had no reason to trust any provider of a school, university, company or family mail server.
Think about it: the majority of people wants to make sure their own administrator, significant other or family member will not be able to read their mails, so it is absolutely logical that they will flock to Google rather than use daddy's mail server.
Same happened with XMPP (Jabber). As soon as Google joined XMPP it became its biggest node in the federation. Privacy advocates try to have an account on ccc.de, but the CCC can hardly bear the expenses to run such a large server. Also, it most likely has been hacked by now and all the social graph of who is friends with whom is available to the agencies.
In the case of social networking the situation is even worse, because the problem isn't only privacy. It's also the capability of distributing millions of status update, like and comment events to thousands of recipients at any second in real-time. The only architecture that is known to handle so much traffic is cloud computing aka big data centralization.
What the Internet desperately needs to even *start* respecting civil rights is *distributed* technology where server nodes have no idea whose data they are moving around and what is inside, where server nodes can be replaced anytime and no server is ever trusted. You may think of blockchain now, but the problem with blockchain is that it doesn't protect metadata, so any observer can see who is talking to whom. So we need something better than blockchain.