Moral lesson of the gift of the magi?
It is that love is stronger than any gift
"The Gift of the Magi" (O. Henry, 1906) is a story of love and affection, and how self-sacrifice is the greatest expression of it. The twist is that while both gifts are rendered useless, the act of giving them is not. This is consistent with the modern saying "it's not the gift, but the thought that counts".