Excuse me, but I was not "railing".
It appears that you may be, though.
The title "Mother of God" when lacking extra explanation which limits that to be mother of the incarnate Christ, is left with imply (at the very least) that Mary existed prior to God, or that she was His "mother" prior to her own self being born. From God's own view, perhaps that is. From our own more limited viewpoints, rather stuck as we are within the timelines of our own existences, it simply could not be that she became pregnant and birthed a child prior to herself being in physical existence.
The term Theotokus (more literally translated into English as "God Bearer", than Mother of God) when it is insisted be used across the board implies that she is mother of that second "person" of the Trinity, instead of in more limited fashion ---be mother of the earthly incarnation of that "second person" of the Trinity.
Did you catch that distinction?
It is fair for one to speak towards the physical side of "things" in this, for among what else is said to be of utmost importance, is that Christ, the begotten son of God, came to this earthly, physical realm -- in the flesh.
Much of the basis for objection and push-back on towards the term "Mother of God" occurring here in regards to Mary, is due to the generally obvious transference of what role Mary played as for the physical Incarnation of that second person of the Trinity to be casually applied to extend and persist in Heavenly realm unto this present day, inducing the fervently pious towards speculation and creation of defined one-going role for "Mary" far beyond and most nearly entirely outside of the monotheistic outlooks of the the original generations' Christians.
But I think I'm done trying to get this point across, for the time being.
Go ahead though -- rant and rave (and rail) on, to your heart's content.
Did you catch that distinction?
I certainly did catch that distinction. And you have fallen into precisely the heresy that the term "theotokos" was intended to combat: Namely, shattering the unity of the Incarnate Word.
It is precisely because JESUS CHRIST IS ONE PERSON--the Son--that Mary is NOT called "the mother of the human nature of Christ" or "the mother of the flesh of Christ" but "the Mother of God."
You have demonstrated once again that those who deny to Mary the title "Mother of God" eventually defend their position by denying that Jesus Christ is one Person with two natures, that God became Man, that the Word became flesh, falling into one or more of the classic Christological heresies.