Oh, where to start?! First of all, Gabriel told Mary that she WILL give birth to th Savior. It was a done deal. No permission or assent was requested. Mary of course gave her assent anyway, and her faith and obedience is to be commended and emulated. But to suggest that she could have thwarted the redemptive plan of God is ludicrous, perhaps even heretical. It elevates a human above God. Second, following you reasoning, the same “hyperdulia” (worship lite?) should be given to the multitudes of Jesus’ ancestors who (by your logic) could have prevented the incarnation by disobedience and thus breaking the Davidic line. Take Noah, by your logic he is every bit as responsible for the appearance of the Messiah as Mary. No ark- no Jesus. Why no hyperdulia for poor Noah? Of course the fallacy here is that God cannot cary out His plan absent our obedience. Scripture is replete with examples of God carrying out His plan despite human disobedience and sin, even using sin to advance His plan. Mary was no different.
Every heard of these two simple words “free will” ? Even God respected a person’s free will to say either “yes” or” no.” It is as simple as that.
God gave humans free will. Individuals are free to either participate in God's plan, or to resist it. If God's plan calls for someone to play a particular role, and that person refuses, that portion of God's plan will not proceed as intended, and alternate arrangements will have to be made. That does not imply that humans are above God, however. An individual standing in the ocean can push his hands through the water, and the water will get out of his hands' way. That does not, however, mean the individual is more powerful than the ocean. Likewise, if individuals want to resist God's plan, they will be free to do so, but God will call upon other individuals to do what needs to be done.