On one level, this statement is definitely true. The Arya that Gendry (Joe Dempsie) meets in the dim yet sultry cellars of Winterfell is not the young woman he had traveled with years ago. She's hardened assassin now. But some tinfoil hat-wearing individuals believe that Arya never actually survived that battle with the Waif (Faye Marsay) in season 4, and that the woman we see is actually just the Waif in disguise. Before you write it off, though, check out the argument.