Hi; in John 6 both Divine sovereignty and human responsibility are mentioned.
This is true.
No one can come to me unless the Father who sent me draws him. And I will raise him up on the last day.
God is indeed sovereign
. Which is why the question formed in the OP is able to be defended by either side supporting their personal perspective, saved by free choice, or predestined, in God's words.
I think ours is a relationship with the highest. As such, what we know to be true in that union is what we will defend as our truth. It is all there in God's delivery of his message to the world. I think it then becomes a matter of what one feels is their place in his bosom as to which side of the information they will cleave to.
We the human race are in the image and likeness of God, having knowledge of both good and evil we are like unto God, (see Genesis), and as such God tells us, he knew us before the womb. When we are his he knows us.
There is no debate, no question. The discussion, or argument, or debate, as we'd like it to proceed if we arrive at this sort of topic, boils down I think to how personally secure we feel in our belief as to God knowing that personal link to the divine as that intimate individuals pondering and introspection concerning their identity; "I am, Christian".