In my opinion, a matter of faith does not require scientific proof. For ages, we have listened to our great epics and believed the characters to be true. In this age, unless everything is scientifically validated people don't accept it. This happens more so in the case of Hindus. The present day Muslim did not see Prophet Mohammed existing 1300 years ago but has no problems accepting him. It is a sacrilege to even consider a opposite opinion. Same with a Christian who may not question JC. Even the non-believers don't go to the extent of making fun of JC or Allah or the Prophet. In Hinduism, even Hindus question the authenticity of Vedas, Upanishads, Puranas or the Itihasas. Someone would say we Hindus are free thinking, liberated and scientifically inquisitive and so on so we question. But to what extent? Only a scientific validation would do? What is the guarantee that Science is not making a mistake. I remember reading an interesting news about a popular mineral water brand in the UAE. This water is extracted naturally from the mountains here and there is an instrument which gives a kind of signal if the impurities in the water exceeds a certain level. The water that is extracted is so pure that the instrument remains silent all the time. From time to time, just to make sure the instrument is working properly, the plant runs it through unclean water.
It is just like the Saraswati river was considered to be mythical until satellite images threw up the dried river bed. There are numerous sthla puranas validating the events of Ramayana and Mahabharata and we cannot just dismiss them as figments of imagination. If they are imagination, then the ancients' imagination is really so wide and huge to weave the kind of stories.