There is no way that the protestant interpretation of Mary's role can be accused of being created out of thin air with no biblical basis.
So often those who oppose the protestant interpretation provide their own by saying "It 'could be' X, Y, or Z...."
What they ignore is that their own argument lacks conviction. If they can state it absolutely, let them do so. Let them say, "Scripture undeniably and unequivocally affirms X.....and here is the CERTAIN proof of it."
amen