Well, it's likely related to the continuing trend of cishet writers engaging in queerbaiting, whether intentional or not. In this story's case, a lot of transfeminine readers would relate to the experience, and some have complained about the rug being pulled out from under them. Full disclosure, I was one of those readers who complained but kept at it because the story was worth a shot. I'm mostly pleased with it, though I am more than mildly disappointed with how few works there are which have a not-conventionally-attractive crossdressing lead who would also manage to be trans representation.
Hopefully that made sense.