Well, for simple reasons. If God in heaven required a woman to become a mother for His Son as someone who will take care of Him on earth why not us?
If the Son of God submit Himself to a mother like Mary all His life on earth why not us?
If the Holy Spirit found His resting place, His Ark on Mary why not us?
No one can love Mary, the Virgin Mother, more than the love of the Holy Trinity. Respect her more than the respect of the choir of Angels.
No one fears Mary, more than the fear of hell.
No truly born again in spirit can claim being truly born again without a mother who gave birth in them. If the Apostles were made children of Mary in Calvary so thus all who went down, carrying the mandate of preaching, must have Mary as their Mother - no exception. Since then onward, the Apostles let Mary in to their homes.
If the Holy Trinity require Mary to wear flesh and blood for Christ to become truly human and humane why cant we wear the love of Mary to become truly human. So, when we become truly human, we can become truly Christ and divine.
The Apostles are not Christlike in the same way as Mary. We can say even that Christ is Marylike in His humanity.
If Mary gave the Son of God humanity, it is the unanimous teaching of the saints and the scripture and being said in the Holy Mass, that the Son of God in turn gave Mary her divinity.
It is the price and payment of the Divine to human that in giving Him humanity He will in turn give man their lost divinity. Does this divinity means becoming a Deity equal or higher than God. No, you are misunderstanding it.
The scripture teaches that the work of the Holy Spirit is to transform the man into human, the human into divine by making him in the image of Christ, as such, the man lives not by himself but Christ lives in him. The old passed away, comes the new - the Christ in everyone. The face of Christ is seen everywhere. The love of Christ everywhere. The love that compels.
Mary's honor is inseparable to the honor of the Son in the same way does the light of the moon is inseparable from the light of the sun. Without the light of the sun, the moon is without light. You cannot remove Mary in the life of a true Christian in the same way that you cannot remove the moon for it is the only light in the darkness of the night.
During the time when darkness fells, Christ told His disciples to WALK BRISKLY WHILE THE LIGHT, WHICH IS HE, STILLS WITH THEM...for when he is absent (materially in the world) darkness will fall, the world is without light but the Holy Spirit and Mary. Who else?
In the absence of the teacher, the teaching is the teacher.
The Christians needs Mary to become truly Christian and human. Christians are meant to be followers of Christ, disciples, servants of Christ. Since no one follows and serve Christ more than Mary - she is the rightful teacher in the absence of Christ as much as she was Christ's first teacher on kindness, love, beauty and obedience.
The Holy Trinity cannot be wrong in electing Mary, then, now and ever. If they and all the saints loves Mary, imitate Mary in serving Christ, why can't we?