I strongly agree. NixOS is a league above things like Ansible that are highly mutable. Also getting started with NixOS really isn't that bad. Just read the wiki and set a few options. https://search.nixos.org/options
The hard part about NixOS is when you need to package something yourself. That can have a bit of a learning curve but since nixpkgs is the largest package repository you rarely need to do it.
If you are running custom stuff you can always start by just using NixOS to run a Docker container. At least that will be a reproducable OS and if you pin a specific image it will be fully reproducible. Then when you want to you can dip your toes into native Nix packages. (It really isn't that bad, just an extra thing to learn that you can defer to start)
Agreed fully! Just got finished packaging up a few desktop apps for the first time on NixOS and it wasn't as bad as I expected.
My biggest issue with Nix (as is everyone's I hear) is the mediocre documentation. It takes a lot of wheel-spinning to get up-to-speed with PKGBUILD or makefile knowledge. A lot of that difficulty curve could be remediated with better, flake-focused packaging tutorials. Surely though, that too will be Coming Soon™.
The hard part about NixOS is when you need to package something yourself. That can have a bit of a learning curve but since nixpkgs is the largest package repository you rarely need to do it.
If you are running custom stuff you can always start by just using NixOS to run a Docker container. At least that will be a reproducable OS and if you pin a specific image it will be fully reproducible. Then when you want to you can dip your toes into native Nix packages. (It really isn't that bad, just an extra thing to learn that you can defer to start)