Nervous managers of the scheduled 2020 presidential debates are shuffling the logistics and locations to deal with the threat of the coronavirus. But here’s a better idea: Scrap them altogether. And not for health reasons. The debates have never made sense as a test for presidential leadership. In fact, one could argue that they reward precisely the opposite of what we want in a president. When we were serious about the presidency, we wanted intelligence, thoughtfulness, knowledge, empathy and, to be sure, likability. It should also go without saying, dignity. Yet the debates play an outsize role in campaigns and...