Yes, you are right here. It's always difficult to know how far down the tree of topics you should go to provide a end-to-end explanation. I tried to call this out in the start of the article. These are the "hard parts" of technical writing IMO.
I sometimes put a list at the top, like "This article assumes that you have a working familiarity with Linux namespaces (link to 3rd party intro to that), veth interfaces (link to 3rd party intro to that), [...]."
