I think that there’s a further point to be made here about responsive or sentimental norms: I know people who have become defensive when going through the invisible backpack exercise—and certainly I myself often have that reaction, even if unbidden—as if another’s asking one to acknowledge one’s privilege is the same as another’s asking one to apologize for who one is and what one does.
The point of the exercise is never guilt. Guilt in this case is a useless emotion, and arguably an inappropriate one. Acknowledgement is not apology: it’s a combination of being aware of your privilege, demonstrating your awareness, and changing your behaviour accordingly. As a white person, for me to be aware of my white privilege and demonstrate that means that I ought also to pay attention to my social milieux and the people of colour in my life, to notice when their non-privileged identities become the source of discrimination, microaggressions, or macroaggressive behaviour. It means that I have to recognize that even when I try to be an ally and an advocate, the fight is one that I elect to continue, not one that I must; therefore I have to commit myself with particular integrity, and know as well when to step back and let others speak for themselves. As a queer person, I expect the same from non-queer allies.
We all have an obligation to acknowledge our privilege, and to work to eliminate the harm that relative privilege or lack thereof does. But since no one is asking anyone else to apologize for having privilege, no one needs to be defensive about who they are. I hardly think it’s too much to ask that we all be supportive of each other whatever our identities, and offering that support does not entail having to hide or say sorry for one’s identity as such.