If you pick any email, and click Edit, Copy as Document Link, and then paste that into Notepad you may see something like
Database - Subject
... where ... is some xml like stuff
Where a sample might be
Rob Berendt - Sample email subject
If, however, you pick a server document from your address book and do the same thing the paste will show the view name instead. I suspect the copy as document link looks for the field Subject in the document properties and, failing to find that, it uses the view name instead. I don't think we have any non email databases with a field called Subject.
You probably didn't notice this when pasting links into Notes email because all you see is some little icon. But if you paste that link into O365 you will definitely notice the difference. I can't see HCL resolving this as it would be too much work to try and determine what field name to use instead of Subject on each custom database.
So, as a design standard you may want to consider using Subject instead of something like ServerName. Or duplicate columns.
BTW, like link still works and will pull up the individual document. The reason being that the XML like stuff will contain a line like this:
And that will differentiate it between a document link and a view link.
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