Secret identities don't exist, not in the way they exist in a superhero universe. It's a contrived and flawed concept which belongs to a different era of comics. As it often happens with this kind of concepts, there's a lot of room for maneuver to force it into any kind of possible metaphors. Think about it as if it was a metaphor for undercover agents, and revealing the ID publicly is clearly dangerous and improvident. Think about it as an occasion to reveal your real being, as some sort of coming out, and it suddenly makes sense. There is not one right answer. One thing's for sure - it is true that public identities have become a rare trope in a lot of superhero comic books. And I don't think that characters really suffered because of it. If they want to make it work, it will.