Because it's like the Holy Grail, since they don't know where he's buried and he was taken to Alexandria after death ...
While Alexander's funeral cortege was on its way to Macedon, Ptolemy seized it and took it temporarily to Memphis.[141][143] His successor, Ptolemy II Philadelphus, transferred the sarcophagus to Alexandria, where it remained until at least late Antiquity. Ptolemy IX Lathyros, one of Ptolemy's final successors, replaced Alexander's sarcophagus with a glass one so he could convert the original to coinage.[145] The recent discovery of an enormous tomb in northern Greece, at Amphipolis, dating from the time of Alexander the Great[146] has given rise to speculation that its original intent was to be the burial place of Alexander. This would fit with the intended destination of Alexander's funeral cortege.
But, why would it? He died in Babylon.