The long-awaited sequel reunites Anne Hathaway and Meryl Streep, piles on the fan-service escapism — and doubles a sober reminder of how much has changed in 20 years A long time ago, in a Manhattan far, far away, a young commoner walked into a magical kingdom named Vogue and took a job as an assistant to Queen Wintour. She eventually escaped the clutches of her regal tormentor and wrote a roman à clef about her experiences. Names were changed, and the story was technically categorized as fiction. But everyone knew who this “Miranda Priestly” character, with her Hermès scarf and sharp tongue, really was. Besides, industry gossip, behind-the-curtain peeks and pure, uncut schadenfreude can move a lot of books. It helps to remember that Lauren Weisberger’s 2003 novel The Devil Wears Prada began life as a form of literary payback, and when the movie adaptation hit screens in 2006, the era of celebrity editors-in-chief and hostile workplaces was still in full swing.…