Mirroring the other comment, but this post really has nothing to do with Nix, so I have no clue where this comment came from.
But anyway, I think Nix has a few things that turn people away:
- New language to learn (which is fairly simple, but gets more complicated when you introduce...)
- Nix flakes?
nix-shell?nix-env? Just looking at setting up a shell, you havenix-shell,nix shell,nix develop, and possibly so many others - The module system, put lightly, is confusing (for when you need modules)
- It's difficult to find which packages are available in nixpkgs (and making a custom derivation is not always trivial)
- Almost nobody documents how to install their tools with Nix (or add it to a
shell.nixor equivalent) - ... and so on
Nix is awesome, of course, but it's far from being the right tool for everyone.