The Nix documentation is what drove me away from it years ago when I tried. I ended up landing on GNU Guix, where I have been for about 5 years now. I found the OS documentation to be much nicer (info pages!) and the decades of Scheme documentation makes the language easier to pick up too.

Seconded! I really liked Nix, but found the language and some of the tooling inscrutable. With (non)Guix I got all the Nix goodness, but in a form I understood much better. If Guix wasn't so good I'd be on Gentoo or Arch.