It helps disambiguate Nixlang from the codebase that includes the Nix CLI and the Nix daemon, for one. It's also an unambiguous designation for the original Nix implementation, as opposed to Lix and Tvix.
A Lix user might well reasonably say they 'use Nix' because they use Nixlang. Thus some people are Nix users but not CppNix users. As Tvix matures, the same will be true of Tvix users.
A Lix user might well reasonably say they 'use Nix' because they use Nixlang. Thus some people are Nix users but not CppNix users. As Tvix matures, the same will be true of Tvix users.