That’s the main crux with NixOS, it does a lot of stuff in the background for you that in my opinion you should know why it’s being done the way it is. As such I consider Arch a good distro for a beginner who wants to learn the inner workings of Linux, while NixOS is a better-engineered distribution that takes care of the system for you. Arch’s goal is to be simple for the maintainers which means it’s very close to what one might consider a “standard Linux”, and its wiki is mostly a documentation of exactly that.