"It is (and, increasingly, was) used to signify that a bibliography entry has the exact same author(s), editor(s), translator(s), or corporate author(s) as the previous bibliography entry."
That is so stupid.
Absolutely does not deserve a new character just for that(especially one that is so unusually large).
Whoever introduced that is absolutely drunk on power.
The only reason that exists is because of a power discrepancy where the people with powers to create new characters are also the ones who do enough writing that they feel such a specific and niche pain.
I mean... would it really be that big of a crime against humanity to insert two or three em dashes if the situation seriously needs it? I already have enough trouble distinguishing an en dash from an em dash.