I mean, literally, that the bits of information secured on the Bitcoin network can be used to represent any kind of information. The Bitcoin protocol is a new kind of internet architecture that simply has a physically constrained state-space.
Instead of an internet architecture where bits of information are trivial to create, it's an internet architecture where the bits of information are intentionally difficult to create and send.
People don't understand Bitcoin this way because they are so used to abstracting away the complexity of machine code and what's happened at the bottom of the tech stack. All they do is focus on modern programming language at the top of the stack.. so they are blind the what's happening at the bottom.