In a less-than-crowded field, Sebastian Coe has distinguished himself as a resolute voice in sport’s rollback of gender ideology. Amid so much hand-wringing about the transgender debate, the president of World Athletics held firm last March in his long-stated belief that biology trumped gender, banning athletes who had gone through male puberty from the female category. How dismaying, then, to find 10 months later that his conviction comes with a caveat.