Regardless of the level a tutorial is given at, there is information that is missing. A well written tutorial knows its audience and contains all the information for that audience.

Sure, I will grant that someone who doesn't know what a computer is shouldn't be expected to follow a tutorial to install PostgreSQL on a headless linux server with proper security protocols in place.

The issue is more that it's extremely easy to assume someone understands what "primitive file operations" are necessary to accomplish a goal, and fail to describe what it is the user actually has to do.

Just because you understand how to navigate a file structure doesn't necessarily mean you have the domain knowledge necessary to make leaps that are frequently present in tutorials.