That was my hunch. I do not think that there was a purva-paksha that itihasa is not history and I also think that such a position was of general concern at his time.
You might want to reconsider your claim "Yet he accepts the basic Mahabharata story as real history, in all its supernatural abundance" then.
At a time when the category of 'history' itself is being interrogated , 'history' as a 'modern' category is being intensely scrutinized through 'post-modern' tools, elevation of 'history' to a higher value vis-à-vis myth and other narrative accounts of past is more and more being viewed as a product of enlightenment age fascination for logical positivist understandings, the tendency of an office to hang on to the obsolete tendency of claiming the assumed superior status of 'history' to certain narratives is what comes of the reported words of the new ICHR Chairman.
Warm regards,
Nagaraj