Most of the services you use on the internet are centralized, but the internet itself isn't. Anyone can host a server anyone else can theoretically access so long as there is a path along which to connect and the user knows the address. Portions of the internet's infrastructure can be cut off from the rest by a sufficiently powerful entity, and most people use the same few DNS servers, but no one controls the whole thing. Internet 1.0 is still running under the surface.
So that helps answer what I was thinking.
There can definitely be a way to have a decentralized system to which it's actors have their actions regulated by a judicial system.