It’s not that the Catholic Church suddenly decided to exalt Mary. It’s that God exalted her first. Jesus could have come into the world any way He chose.He did. He chose to be conceived by a woman and He created her.Mary was truly His mother. The Magnificat of Mary also known as Mary’s Canticle.The words Mary proclaims to her cousin Elizabeth(and us)
My soul magnifies the Lord And my spirit rejoices in God my Savior; Because He has regarded the lowliness of His handmaid; For behold, henceforth all generations shall call me blessed; Because He who is mighty has done great things for me, and holy is His name; And His mercy is from generation to generation on those who fear Him. He has shown might with His arm, He has scattered the proud in the conceit of their heart. He has put down the mighty from their thrones, and has exalted the lowly. He has filled the hungry with good things, and the rich He has sent away empty. He has given help to Israel, his servant, mindful of His mercy Even as he spoke to our fathers, to Abraham and to his posterity forever.
Remember,from the beginning God said,He would put enmity between her and Satan. It would have to be total enmity meaning that she would be without sin. Jesus saved His own mother and she was immaculately(without sin) conceived.