When the transgender fever fully subsides, it won’t be because of how celebrities like Kiera Knightley respond to idiotic questions about it. But it’s telling when celebrity windsocks no longer feel obligated to pay ritual fealties to social contagions, because social contagions rely on ritual fealties to survive. In a Decider interview published last week, Knightley — who voices a character in a forthcoming audiobook recording of J.K. Rowling’s Harry Potter series — was asked if she was “aware” of the fury directed at Rowling and, by extension, the Potter franchise for Rowling’s “ongoing campaign against trans people.” (By this, the interviewer meant Rowling’s insistence that men cannot become women and should not be enabled to invade private women’s spaces.)...