I understand that a shortcut for Copy Page Link is not possible because it is not present in the main menu, only contextual menu. Is it for this same reason that System References Keyboard Shortcuts also does not work?
Now, why is Copy Page Link any less important than say, Edit - Copy Item link? Actually for research I use this a lot, but so far no such keyboard shortcut.
No, Control-Option-Command-C is the shortcut for Edit > Copy Item Link. If the link created with the shortcut opens the PDF on the page that was selected when the shortcut was used, that is happenstance. Sometimes the link will open the page one imagines because that page was the last paged viewed, but that is not a persistent result.
The link created with that shortcut is not a page link.
Here is what a link created with Control-Option-Command-C looks like:
Note the appended “?page=12” that Copy Page Link adds. (Because pages start at zero, “?Page=12” is a link to page 13 of the viewed document.) There is no keyboard shortcut for Copy Page Link.