The ad-hoc solutions you're talking about are often highly usable, a virtue often forgotten by software evangelists. Nix's learning curve will keep away people

The ad-hoc solutions you're talking about are often highly usable, a virtue often forgotten by software evangelists. Nix's learning curve will keep away people who are disciplined in avoiding yak-shaving, as the language specific version enables productivity now. Maybe adding a layer on top of Nix, like create-react-app is to webpack, can make it a better option for immediate productivity oriented developers.