The language itself has no type enforcement, the type checking is implemented within nixpkgs. This might seem like pedantry, but it really matters for things like LSPs (text editor autocomplete). I think that's what scares some people off: it's like OG Minecraft, you need to have the wiki/search.nixos.org open while you are doing your editing.
That being said, the type checking goes much deeper than what the windows registry does - e.g. it won't allow you to enable conflicting services - like grub and systemd-boot - at the same time.