No writer has any control over what readers do with their works, nor how they interpret them, once they are released. If they wished for such control, they would have to leave them in unpublished manuscript form at the bottom of a drawer. Many do just that with some or all of their writing, for fear it will be misunderstood or twisted.

But once a book is published, the final act of creation lies with the reader. Tolkien's wish not to have his work 'allegorised' is naive, to the extent of being disingenuous, I would suggest, above all in a learned scholar of mythology. Myth and stories are always allegories, whether intentionally or not, since they, like The Shire, do not exist within a vacuum.

I would agree that it seems somewhat absurd to see TLOTR as a right-wing treatise. Given its immediate historical context, it seems far more explicitly a fantastical reflection of the Second World War and the role of Britain and its allies in confronting both the appeasers within their borders and the growing horror of Nazi Germany and Japanese imperialism.

No, it is not meant as 'an allegory' of that global conflict. It is its own story in its own right. But neither writer nor reader can help but be consciously and subconsciously influenced by that geopolitical and philosophical context, whatever they may claim.

Any claim that such interpretations are 'treason' seems very strange. Treason presupposes a prior oath or duty of loyalty which has been breached. I don't see how this could possibly exist in a reader of a novel.

There is, perhaps, a duty towards literature itself on the part of Tolkien, as writer and literary scholar, with which any vain dictate as to the permitted interpretations of his work would indeed conflict.