Who, me? I was simply drawing a conclusion based on the fact that the pronunciation of
Xanthippe is "ZAN-tip-ee", the pronunciation of
Xena is "ZEE-nah", the pronunciation of xylophone is "ZY-lo-FOHN", and the pronunciation of
Xenon is "ZEE-non". All words are ancient Greek or from the ancient Greek, and in all, the X is prounced as the English Z. That, to me, would indicate that the proper pronunciation of the X in
Polyxena is also Z.