Hindu nationalism is a reality in India - it resulted, to some degree, in the BJP winning such a large majority and it may (if it isn't already) have a major impact on India's domestic and foreign policies.
From a purely Pakistani perspective, allowing Indians to represent the 'Hindu Nationalist' point of view on this forum is important in terms of us learning what it represents and better understanding the potential impact on Pakistan.
That is not to say that the mod team won't step in if it gets too out of hand in terms of attacks on Pakistan/Pakistani history, but I don't agree with an outright ban on Indians expressing Hindu Nationalism.