It's just splitting hairs.
If you were to go by what it really does you would say drawn, or not drawn.
While it has the advantage of not being seen, it also has the feature of not being rendered.
You're saying it should say "visibility: visibility/invisible", but that doesn't fit either.
If you were to keep visibility you need "visibility: visibility/invisibility"
"Visible: visible/invisible" makes more sense imo, and is correct grammatically, it's just not expected in its context.
"Drawn, not drawn" is probably confusing to a beginner.