For 70 years, Egyptian authorities made requests to Germany to return the bust, citing that it is important to Egyptian national identity and that Borchardt removed the artifact under false pretenses.
I find this case similar to the return of the Machu Picchu collection from Yale to Peru. Both instances date back to 1912, and both source countries accuse the archaeologist of removing the item(s) under false pretenses. If Germany wanted to return the bust it could possibly allow for a cultural exchange, but Germany already has scholars in Egypt promoting Egyptian history. Unlike the Machu Picchu collection, the case with Egypt concerns the one object that stands alone as a symbol, so much so that many flock to Germany to view it.
Given that the object has been in Germany for more than a century, and in good care, should Germany return the bust of Nefertiti to Egypt? Would Egypt even care if the bust was not considered an artistic beauty? Would the bust be safe in Egypt given recent events in the country?