Earlier quoted context omitted.
So IPFS with cryptography? Although, since Keybase still has a copy of the data, its closer to Dropbox with crypto. https://ipfs.io
I don't think it's distributed in the IPFS fashion, right? Which makes sense, of course, since Keybase is a funded startup that needs to capture value... and, well, centralized file sharing is a more straightforward solution, too. The file system thing seems really cool and useful. I'm a fan of Keybase and will recommend this to people with whom I need to share sensitive data. It'd be interesting to hear the Keybase…
As an infrastructure provider, they open source the client software and design it to trust the server as little as possible. They also endeavor to document the behavior of the server so that, in theory, you could build your own Keybase-compatible server.
As an economic entity, they're positioned to tackle the issues that open source projects usually face, like support, development resources, UI design resources, and "where do you put all of this encrypted data" by getting their most needy users (mostly businesses) to pay them.