The problem isn't really that "nix" can refer to the tool or the language. (e.g. it's not really a big deal to distinguish Java's compiler, VM, standard library

The problem isn't really that "nix" can refer to the tool or the language. (e.g. it's not really a big deal to distinguish Java's compiler, VM, standard library, or language; and I'm not sure why you'd want to use a name other than "Java" for these). I think it's more ambiguity around statements like "Nix is difficult to use". The Nix package manager, and the Nix expression language themselves are quite straightforward. (Even if applying these to what you want to do can be difficult). Whereas, the main repository of packages, Nixpkgs, is often inconsistent or otherwise confusing, and can be difficult to navigate. So you'll want to get something done, and be shit out of luck.