Calling Mary “Theotokos” does not deify Mary at all.
You are not accurately describing what it means.
In fact if you understood what it means, I bet that YOU even believe she is the Theotokos. For trinitarian Christians it is an uncontroversial fact.
What does Theotokos mean? Theotokos means GOD-BEARER.
It simply means that Mary had Jesus in her womb, and gave birth to Jesus — and that Jesus was God. It DOES NOT mean that God originated from Mary — God was uncreated and existed for all time.
So when you say Theotokos is deifying Mary, that is completely false.
Do you believe Jesus is God? Do you believe Mary had Jesus in her womb and gave birth to her? Do you believe God existed at all times? Then you believe the same.
Incorrect... Mary would be called Christotokos, like Nestorius proposed and the RCC rejected, if the RCC believed the she were merely the Christ Bearer. Theotokos means bearer of God... putting her in the category of the Devine.