No, because that is precisely what Judaism believes. The difference between Gnostcis and Jews is more than just a label. Gnostcis believe that those souls living in the flesh are souls that have sinned and were cast out of their natural spiritual existence and placed into a fleshy "dungeon." Judaism doesn't believe that at all. Judaism completely rejects the idea of the original sin having anything to do with any change in human nature.
If Gnostics were right, then man and angels were both noëtic spirits. The way Alamo Girl describes Adam, originally existing only as a spirit, makes him an angel who was given dominion over earth.
I suppose one could find biblical support for this, given that Adam is referred to as the "son of God," a title also given to angels, but it doesn't epxlain why were Adam and Eve (a female angel???) given bodily "prisons" for their sin, and the [other] fallen angels were not.
I've discussed this before with A-G. That's not what she believes, unless I'm seriously mistaken. She believed Adam had feet in both those worlds, a with their existence being a much larger footprint on the spiritual side than now. Which is quite reasonable. God walked in the garden.
Of course not. But the above observation seems not to grasp a far more fundamental principle of Gnosticism, i.e., that God is directly the author of both good and evil. "Evil" is everything worldly; thus the Creation itself is "evil."
Christians believe, OTOH, that God is Goodness itself, and created a world that was "very good," albeit not "perfect." (If it were "perfect," it would be static; moreover, human free will would be pointless in such a world.)
Christians believe that evil is "merely" the absence of the good. God is not the malefactor of evil; only creatures made in His image — possessing reason and free will — can be such.
You wrote:
The way Alamo Girl describes Adam, originally existing only as a spirit, makes him an angel who was given dominion over earth.I don't read Alamo-Girl that way at all. Angels and humans — though both are, as you say "noëtic spirits," and as such Sons of God — are still distinctly different orders of divine Being — one "heavenly," the other "earthly"; one discarnate, the other incarnate.
God specified Adam (Man) in Genesis 1; brought him into Being in Genesis 2, and then gave him dominion over the earth. When Adam fell, he did so as a man, not as an angel — for he never was intended to be an angel.
It seems another characteristic of gnostic thinking is the absolute separation of the spiritual (seen as "good") and the earthly (seen as "bad"). That is, there can be no interface between heaven and earth in principle. But of course both Jews and Christians believe that God is constantly active in His creation — that the Creation of the Beginning is constantly ongoing. IOW, the "earthly" constantly resonates with the "heavenly."
Just some thoughts....