even those privileged by them – those who are cisgendered and heterosexual, as the song’s protagonists may be, are more harmed than helped by the restrictions imposed on the ways they are allowed to be children, to be boys or girls

Very much agreed! (I do love Dar, in all her earnest glory.)

And yes, the more I think about it, the more I think this song really is perfect for Amy, and for the whole ambiance of series 5: faith in the power of memory and imagination and all that.