Troons never seem to understand (or perhaps they do, and just refuse to accept out of spite) that male privilege, such as it is, is conveyed onto male-presenting people by society. It doesn't exist in a vacuum and it's not some innate thing tied to your subjective gender identity that you can get rid of once you Troon out. So, much as it may blister his balls to hear it, Dave presents to society as a man in a dress. Society may think he's a faggot or mentally ill, but they still think he's a man and still convey male privilege onto him.
It's the same reason white privilege was given to octaroons and other people with some major, but not majority, amount of black blood despite "one drop" rules being in place during Jim Crow. What you present as, what you are perceived as, is what determines your place in society, not wack-ass "self identity" shit.