The rest of the thread (at least my posts) was about the Share menu item, not the Share a OneDrive Link menu item, which is a different thing.
Neither of your screenshots has a Share item (even in Notepad), which fits with what I said above. If you right-click something in File Explorer, you should see the Share item. It only appears in File Explorer, which you didn't screenshot.
As for Share a OneDrive Link, that appears in all three of Opus, Notepad and File Explorer here when in the OneDrive folder. (I have 3rd party menu items hidden by default, so I need to hold shift to see if, FWIW.)
It also does absolutely nothing in all three programs when I select it, such is the quality of OneDrive and Windows these days.
Please link your account.