I don't know what "nutso" means (I don't think we use it here in the UK), but it doesn't sound very complimentary. Like you, I don't agree with ideas that the forbidden fruit was figs or pomegranates, but unlike you, I see no reason in Genesis for saying that the tree of the knowledge of good and evil was not a physical tree. God's command in Genesis 2 was:
(Gen 2:16-17 NKJV) And the LORD God commanded the man, saying, "Of every tree of the garden you may freely eat; but of the tree of the knowledge of good and evil you shall not eat, for in the day that you eat of it you shall surely die."
You seem to have God saying, "Of every physical tree in the garden you may freely eat, but there is a non-physical tree, the tree of the knowledge of good and evil, and you shall not eat of that."
"Nutso" means "blind" meaning you STILL focus on physical fruit instead of the spiritual meaning of the story.