It’s been more than 20 years since the world fell under “Harry Potter’s” spell — but hindsight is also 20/20. And some fans of J.K. Rowling’s wizarding world, including Jon Stewart, have been spotting problematic stereotypes that they either missed or dismissed the first time they read the books or watched the movies. Alas, this isn’t a problem exclusive to “Harry Potter.” The fantasy genre has long had an issue with racism and representation. But this week, a December 2021 clip from Stewart’s Apple TV+ AAPL, -1.20% podcast went viral. It featured the former “Daily Show” host pointing out how...