"transracial" is just a repeat of transtrenders, where the ideology circles around to become the complete opposite of its original intent. It opens the door to anyone becoming anything. If identity is entirely a social construct, anyone unhappy with their lack of privilege can simply become a white dude and problem solved. Nothing's stopping them. If you run with their base assumption that these things are entirely social constructs with no biological component, they have no reason not to simply trans into the most privileged class possible.