Did Ramayan and Mahabharat actually happen or is it just a moral story?

Did Ramayan and Mahabharat actually happen or is it just a moral story? Let me tell you a story. Let at some point in the future, somehow mankind ended, like shown in the movies. But only a few hundred people survived on an island. They didn't had any food or modern technology to survive. So they started living like early man. In order to retain the information of human civilization, they passed on the knowledge of human history like astronomy, mathematics, moral values, medicinal knowledge and history including world war 1 and world war 2. All of them were translated orally, in English. After 500 years, their population multiplied. The civilization also discovered writing technique. So they wrote down whatever they remembered or retained, as told by their ancestors about the human knowledge, in manuscripts, in English. Over the next 1000 years, the thing that was supposed to be history, science and philosophy took the form of a religion. Those who believed in the history and science were called to be the followers of that specific religion. As the years passed, variations in language came and most of the people forgot the English language. Finally, in the year 4000 A.D., the then human civilization attained 20th Century like technology. Soon the question of the manuscripts and religion were brought to discuss among the scientists, whether they were true or not. One scientist said, "Lol, how could such an ancient civilization exist 2000 years ago.” Another one claimed, "You mean there were flying machines which dropped atomic bombs in world war 2? How could it be possible? We invented aeroplanes and atomic bombs recently, how can they exists before 2000 years ago."