True enough. But to say that God is not a demiurge is rather self-evident, isn’t it? And it begs the question by assuming that only a demiurge would create de novo. (As if anyone knew.) I wonder what the point was? It’s hard to believe these were prepared remarks. It’s understandable when such things are said spontaneously.
The language of the demiurge come from the Gnostics, and was actually used of Christ by them to separate Christ from the Godhead. By using the “demiurge/Creator” division, I think he is saying that God is superior to creation, and not vice versa. However, I am not a papal apologist, not pretend to be one.