it feels like the biggest thing nixOS could do to encourage adoption is remove every section about the nix language and relegate that to a quick reference with links to the nix language docs. It's incredibly hard getting people to see past that and realize it doesn't matter until you need it if you're already used to harvesting configs to make your shell pretty or whatever when it takes up like two and a half chapters.
as for the language, just treat it like any other language you don't know and go how to <thing i want to do> in <language i do know> with <language I dont know>
https://learnxinyminutes.com/docs/nix/ is way better at what you'll actually need to know in the short term if you even need to touch nix as more than a config language, and in the long term you'll know what you're doing enough to learn the rest easier.