Current web technology typically sees one entity controlling the data; if you sign up for a website, your data goes in their database. That's due to the common stack we all build on: some form of API/web server, some form of SQL/NoSQL database, some form of client. If we had a world where developers could simply and freely implement services on top of a different paradigm, we'd stop having to worry about big central entities like Facebook, Google, your local computer store, whoever -- being able to sell your data. They simply wouldn't have it. I'm not sure what that paradigm is, but IPFS, Secure Scuttlebutt, Solid, the Dat Project etc. are all interesting takes on what a solution to that problem might look like.
At the other end of the spectrum is governance, which is something sorely lacking, and allows these misinformation campaigns to spread so freely. Do we still have to worry about governance in a world where we own our own data? Yes, probably, if the surge of illegal and genuinely nasty content like Child Pornography on the new big distributed networks (eg. ZeroNet) is any indicator. Censorship is a spectrum, and while I can appreciate sticking to the view that free speech is best for all, there are some behaviours which society has mostly agreed are objectionable.
The current paradigm of each social service provider essentially being a self-determining fiefdom isn't too dissimilar to how humaity's always done things, I guess (for instance, different pubs/bars will have differing clienteles and degrees of socially acceptable behaviour), except for the scale -- which unfortunately probably does merit a change in how our current major sites are run (YouTube and Twitter in particular seem like they've been gamed incredibly well by cynical parties). I don't know how we solve this problem, but better technical underpinnings might make this a simpler problem to solve. Independently, however, I note that there are places like https://social.coop where they're trying to take that problem on head-first.
It will be interesting to see what the next few years of the internet look like. My hope is that we see some of the people interested in this problem start focussing on normal people instead of other techies; suggesting to my friends that they move to Secure Scuttlebutt is pretty hard, as the majority of them really only use their phones (or tablets).
Personally, I think something that tied together messaging and an event invitation/calendaring system would take a massive knock out of the people who are only hanging onto Facebook for those two things, but that's still a techy view of "kill centralisation" and not a social view of "how does that new platform get governed?".