Because it was fallen individuals who, as the lead post notes, began to deify her starting a couple hundred years after her death and over the centuries got worked into a frenzy until someone said “hey, wait, the whole point was that she’s a fallen sinner just like the rest of us, and blessed & humbled that God would choose her”.
Read the lead post, not just the headline.
No one has deified Mary. She is the Mother of God and, as such, has always been held in very high esteem. Without her "yes", you would not have a Savior.
As for the absurd notion that Mariology emerged from monasticism, the earliest image of Mary is a fresco dated about 150 AD in the Catacomb of Priscilla on the Via Salaria in Rome that shows her nursing the infant Jesus on her lap.
Situated in what was a quarry in Roman times, the Catacombs of Priscilla were used for underground Christian burials from the late second century through the fourth century. And for those who have lost touch with history, christianity in Rome was practiced underground until the Emperor Constantine, by means of the Edict of Milan (313), set forth toleration of all religions, including Christianity, which ended the persecution of christians.