Personally, the stepping stone I needed to know about is Nix Home-Manager, which basically allows you to manage your dotfiles independent of the distro. From what I understand, if I do switch to NixOS, I'll continue using this code with just some minor tweaks.
But yeah, I agree with the verdict in the post. I like it a lot, but I would not have made it past the initial learning curve, if I didn't happen to be a software engineer. Sysadmins will probably be able to figure out how to put it to use, too. But it's just not for non-technical Linux users.