Yes, he is. But in saying “mother of God” when people are insisting that she was the mother of him in godly form as well as human form, and when there is much confusion on the trinity, “Mother of God” allows too much further confusion.
You are still separating Jesus, calling Him “godly form” and “human form.” This was the error of the Nestorians. You can’t separate the natures!
The phrase “Mother of God” is designed to tell us more about Jesus than about Mary. If she is the “Mother of God,” then Jesus, in the flesh, is God. The actual Greek word “Theotokos” literally means “God-bearer” as she bore God in her womb. Hence, she was not just the mother of a human being, but of God made Incarnate. “The Word became flesh and dwelt among us.” John 1:14a
What is the confusion on the Doctrine of the Trinity?