People have a right to think of themselves however they wish. Some are superheroes. Some are vampires and werewolves. Some people in their own minds live entirely in Middle Earth. Some children believe they are kitties. The serious problem is when the deluded are accommodated. Then the sickness spreads throughout the entire system.
There are some people who believe they are neither male, nor female, nor hermorphradites, they live in a world entirely in their own heads. They are no different from someone who declares that they are Hobbits in their own minds. It's okay for them to be a Hobbit if they choose, but it doesn't mean the building code should be changed to provide that all homes have round doors.