f what would happen if every tom, dick and harry is given the moral and ethical authority and justification to interpret the quran for himself
But actually we are given that authority. Or where does it say that only such and such a person can interpret or authorize interpretations of Qur'an. Everybody does it, even though they may think that follow somebody else. They follow that which arranges them most, whatever else they may tell themselves about their reasons. Or how do we know whose interpretations we should take as authoritative. Following somebody else's interpretations we only take an alibi for assuming our own responsibility. But in fact we are choosing.
Salaam