Its irrelevant to talk about historicity of Ram or Ramayana in this issue. The question here is about an EXISTING MAN -MADE BRIDGE. If this bridge is really man-made then IT MUST BE PROTECTED. Because this will be a huge 'coincidence' with Ramayana story.
The focus of debate has to be whether its MAN-MADE or not. Not that who made it ! Becoz whoever made it, the bridge is an ancient monument of India !!
And, IF its really man-made, then its the bridge which will be a historical evidence of Ramayana, not the other way round as ASI is trying to say !!