A lookup table of normative specifications of CLI arguments would also be Reference.
So they are not synonymous.
To be clear, I'm not advocating for navigation that must always have this structure in cases where it's redundant. I think people should do what makes sense. But I think it is nevertheless useful to not mix the different categories.
Depending on the docs theme, it can require clicking through to get to it.
It is a minor annoyance.
edit: Also gonna tack onto this that my original comment reads way more acerbic than I actually feel. I was sleepy and didn't proofread for tone like I normally do.