>The tension/problem as I see it is this: we need distributed networks, where people run their own services, and are servers as well as clients, but at the same time a large proportion of people do not or cannot run their own services. Solving that problem seems key to me--have people act as servers without realizing it (maybe something like with torrents).
We already have a model for this: email.
You and I can use whoever we want as email providers, including hosting our own, and if you don't think I'm a trustworthy provider, you can drop my messages.
The system isn't without it's corner cases, but it's certainly proven to be a robust model over the last ~30 years.
The only thing it requires is standards. We already have one for facebook messenger: XMPP. Facebook and Google used to support it, but they both shut it down because they wanted to lock their users in harder. We have CalDav for events, but again, none of the big players want to know about it.
We could have a "social status" standard, allowing you to send a robustly versioned life update to other servers from whatever social service manager you'd prefer, but you and I know that no amount of user outcry could persuade any of the major players to adopt it. Network effects, peer pressure and social expectation (e.g. please submit a snapchat along with your job interview) power their meteoric growth.
What we need is a "Regulating the Gauge of Railways Act 1846" for the digital age. We need international bodies to review software that has become mandatory to the modern world, distill it down to a set of living specifications, and then ram it down the throats of software vendors.