its weird how everyone, really, has multiple names that are used in different contexts and that many (most women, for one) people will change their names throughout their lives. like a guy might be called bobby by his friends robert by his boss mr burton by his co-worker he might become burton-smith after he gets married, rob at school, he might be robby to his mum, he might have the pen name of burton ellis, and he might be analdestroyer94 on one forum and forallthatsgood344 one another and that is all perfectly acceptable. people have different names and identities in different contexts and these change as they grow throughout their lives.
but then when trans people want to change their names, or young trans people have multiple names for different contexts everyone starts to get a bit weird about it.