One: a chain of specialized Posix programs would work for that. You would have to be someone who can manage a chain of specialized Posix programs, though.
Two: serving as a general-purpose stateful HTTP client is a subset of what Urbit does, though an important subset. It's also a server on a public network.
The second problem can also be solved with Posix programs, but it pretty much seals the requirement for a trained professional. It is possible to imagine a high-usability personal Linux (Sandstorm, for instance), but not really a high-usability general-purpose Internet server (at least if it implements social apps via decentralized protocols).
(In fact, it's not even clear that trained professionals are comfortable with decentralized protocols -- see under, Google doesn't even want your XMPP traffic, etc.)
Urbit may or may not be the perfect solution, but I think it's clear that if ordinary humans are going to have their own personal servers, they're going to need some kind of new system software.