The epic of Gilgamesh is a fiction story
Let me see if I understand.
The Epic of Gilgamesh is fiction. The Epic of Gilgamesh is good.
The Bible is fiction. The Bible is bad.
What logic did you apply to come to that conclusion? All books that last 400 years or more are in the same category. Labeling ancient literature as defective in anyway is bold but stupid. There are reasons why some literature survive and most literature is forgotten. Do you care to take a stab at why that is? I'll give you a hint, it probably isn't because they suck.