It seems that people needed a special revelation (in addition to the Holy Writings) in order to understand and/or be filled with wonder at the birth of Jesus.
The shepherds saw angels and Gods glory in the sky.
The Wise Men a star.
Mary and Zacharia received a visit from the angel Gabriel.
Simeon experienced a direct revelation from the Holy Ghost.
We do not know how Anna received her prophecy.
We do know that she was a widow for eighty four years, serving in the temple, worshipping, fasting and praying night and day.
Elizabeth's baby lept in her womb, and she was filled with the Holy Spirit.
Why do we look down on special revelation of this kind in our time?
It seems that those folks needed it.
Why wouldn't we?