A possible comeback would be to ask whether or not that scripture is a prophecy or not, to be fulfilled in our time. If the answer is no then he is simply speculating and we can say anything could happen when we speculate.
They seem to forget that these stories all led to the one outcome, their demise and the bible goes on to tell us it was completely replaced by something far greater, by Jesus himself. Did God set up this new kingdom arrangement only to see it partially fail like the old arrangement?