Well, if you talk about naming X and whether it is reasonable, the name of X will be known to more and more people. So one side of the argument seems to loose in any case. I do think it would be better to leave him pseudonymous, if that is his wish. I can comprehend why telling a name is preferable for writers to enable readers to check the story themselves, which gives the press some credence. But I think the current climate would lead X to write differently and perhaps less controversial. Pseudonymity or anonymity can be very advantageous.