Hot take as a NixOS user that uses Nix for work: "all" we need is a much better, sound, statically typed language to build better abstractions with.

The only hard requirements I can think of are algebraic data types with exhaustive pattern matching to go with, row polymorphism, purity and good inline documentation support.

I don't know if a good enough hostable language exists or if it should be a new version of Nixlang, but almost every single annoying problem that makes me go "Nix is getting in my way" can be traced back to the lack of a good, powerful type system leading to a house of cards situation whether it comes from nixpkgs or entirely of my own making.

Perhaps something like heroku buildpaks (https://github.com/railwayapp/nixpacks ?) would help devs get on the Nix train.