It looks like Ram concept was stolen and new version was created from Jain mythological stories. But in Jainism Ram is not 17 million years old, or he doesn't speak sankrit. It clearly indicates that brahmin did not leave any chances to copy from Dravidian Jainism of this country which is original religion of Bharat sinc3 5000 years old. Even good thing, like literature, god, concepts, temples, Karma theory was stolen from jain scriptures and copied to brahminic religion. Can we safely say Brahminic religion is off shoot or a cult born from Dravid culture(jain culture), ofcourse Brahmins retained some of their own theories of casteism and social norms like dowry. However today dravidian jainism is 0.001% of our population and hence dravidian jainism is considered part of hinduism. Did Ram temple was built over Jain temple (ayodhya), yes it is, something like many 1000s of temples converted to hindu temple since 800 A.D. Rest of Gods created by Brahmins are simply avatar of Jain gods of dravid culture. Please do not mix Aryan Jainism of present form.
