..." there is no Original Sin since Adam and Eve are myth." "....
The need to re-interpret our concepts of 'original sin' is something that is demanded by our Scriptural understanding that, yes indeed, the authors of the Genesis story were inspired to use a myth literary form.

Since teaching is  now 'the church teaching', theologians need to explain how this affects our 'doctrines' of 'original sin' and the way we speak of 'human nature' and  even death and its 'cause'.

Original Sin is sort of a 'test case'. If we can acknowledge that we got side-tracked on THAT –– by Paul and Augustine and theology through the centuries –– and now have been given a knowledge and understanding of Scripture that demands a change in our theology, it will entail a change in the way many people look at 'dogma' and theology and the potential for a growth and development in our understanding in other areas as well.

Starts with a simple fact: If 'Adam and Eve' did not exist, neither did their 'sin'.