Because with the story of Adam and Eve and the resurrection, the parting of the seas, David and Goliath etc, they are told as if they are historical events... not visions, not parables, and not symbolic. For me, still, the easiest explanation is that they are myth.
When Jesus told the parable of the Good Samaritan, he spoke of all the characters in the story in a historical setting as well. But was the point of the story to be explaining history, or about a lesson in the story's characters? That is the real meaning of mythology. Myth doesn't mean just wrong facts. A myth is a story, or a combination of symbols and signs all combined to communicate certain truths.
Mythology is a vehicle of communication, that tends to be much more effective at imparting truths than just stating facts. The reasons for this is because they engage the imaginations and the emotions of the listeners. This is a more effective method of learning than just raw facts. This is borne out by neuroscience, incidentally.
The Adam and Eve story continues straight into the continuing story that leads to Noah, Abraham and Joseph. All told as if those things were real, historical events.
Historical fiction. Gone with the Wind cites the Civil War, and the Civil War really happened. But did the events in the novel actually happen, or were they a story about something else, whose purpose was not to be a book of history in the sense a modern historian attempts to write events into a chronology for the greatest accuracies for the sake of posterity?
But yes, what you cite is Jewish "history", in the sense of origin myths. These stories are a combination, a collection of myths and actual recalled histories. King David and the two kingdoms did actually exist. However, did Moses, did Adam and Eve in the same sense as David? Very unlikely, in that this "history" was written thousands of years after the supposed events, not based on documents, or evidences, but upon the stories told and passed on from folk tales to the priesthood, to a written form.
While they do serve as a "history" in the minds of those listening, the import of the "facts" of the story are secondary to the the
sense of identity that these are meant to impart. It's that sense of self or group identity that is the actual intent of the stories, not to record detailed and factually historic events from a dispassionate historian's point of view. These are origin myths, these are the tales of self-identity i
n order for a group of tribes to come together through a shared mythology. That is their import and significance, and the reason they were written in the first place.
I have absolutely no problem if you tell me it's all fiction... just stories made up by an ancient people and filled with supernatural things supposedly done by their God.
Not "just stories". But a portrait of their own significance as a people united under a collective tribal deity. In this sense, they are the collective imagination, making a greater whole than just the sum of the individual parts. This can hardly be minimized.