What I often find is this “ought to know” treshold. Parent comment user is probably familiar with lingo you are not. Documentation often assumes a certain level and a writer does not imagine a less capable user.

Yes, the Nix community has great reference docs for people who already know how things work, for most things imo. At the same time, it isn't always obvious enough where to find a good introduction to terms and concepts used. But materials of that kind are increasingly available and general gaps are being filled with a lot of focus lately.