If you want to philosophize about gender, you'd best prepare yourself for my response!
Judith Butler avoids dualism. She follows Merleau-Ponty's view that mind and body are intimately intertwined. Thus she grants equal status to each: the body and mind need each other, and neither is inferior or superior to the other. For her, bodily behaviors express our gender identities. She focuses on public activities accepted by local communities. Now, she still accepts that we have a desired self-image, a mental representation of our desired body, and this desired self-image differs from the person's actual body in cases of gender dysphoria. Pre-op people with gender dysphoria identify authentically with a body different from the one they have before gender reassignment surgery. But I don't see where she claims that the mind is superior to the body. She would just say that people with gender dysphoria want bodies that accurately express their authentic identity. And mind constitutes personal identity as much as the body does.
Let's assume for the sake of argument that Butler agrees with this view.
I deny that what you call the modern materialist perspective entails that we don't need to trust the empirical reports of people with gender dysphoria. You claim that, if we affirm the equal status of the body and mind, then we don't need to listen to the mind any more than we need to listen to the body. But remember: what you describe as the "mind", Butler and I redescribe as a person's representation of the body that best expresses who they really are. When an AMAB person says they identify as a woman and have gender dysphoria and that gender reassignment surgery would allow them to have the body that authentically expresses their identity, I believe them, not because I value their mind over their body and consider their mind a truer expression of who they are than their body but rather because I respect them. Because I respect others, I accept that only one person can know my gender and that is me. The same goes for everyone else. I trust a person's reports that they have gender dysphoria and that their authentic identity is a man, for example, because I know no one can get their own gender wrong. The issue is normative and epistemological, not metaphysical. Other have said this, but it bears repeating: TERFs and GC feminists make the mistake of assuming that they can know another person's gender better than the other person does. But this is why I emphasize that we trust the other to express their authentic gender identity: for my authentic identity is the identity truest to myself. And only I can know what's truest to me.
Isn't this just conversion therapy though? It seems like you want to change the minds of transfolk so that they don't think they're trans anymore. Why else would you want to change the mind of a person with gender dysphoria about their authentic gender, the identity only they can know about?