“Catholics call Mary, *Mother of God*. That deifies her.”
Actually, that title was given to her to deify Christ. There were some Christians at the time that denied Jesus was “Emmanuel”.
Then the best course of action would have been adequate teaching out of Scripture, instead of renaming Mary, making her into something she isn't.
Renaming Mary from *mother of Jesus* as the HOLY SPIRIT named her, into *mother of God* does nothing to correct any confusion about who Jesus is and was, and does everything to add to the confusion about who Mary is.
And based on the prayers offered to Mary by many Catholics, which can easily be found by the most cursory internet search, it not only led to confusion about who she is, but outright idolatry on the part of many people, including some of your very own popes.