It's almost as if only Git is distributed, but people sold out to Github for convenience. Too bad Git lacks a distributed bug tracker and wiki system like Fossil. Guess Github has to fail a lot more for things to change.
Nothing is built into git to let it actually run decentralized: there's no server or protocol where someone can register say, an identifying public key and then just have a network of peers all communicate updates to each other. It's even pretty damn unsafe to just run a repo through basic file-sync (I do this for myself with syncthing with bare repos in a special folder, which seems to work fine but I'm hardly loading it up to chase down why it doesn't).