Well, Nix is probably never going to be usable by non-developers and is very far from production quality for any kind of infrastructure. I mean theoretically you can use it in production if you avoid nixpkgs and make your own package repository with your own packages and your own tools. Playing with it on desktop is fine, although you can't get far without learning the language, reading sources and doing some functional programming.

Still, Nix should be at least an inspiration for next real world package managers.