I think the biggest issue in this debate, about " cis passing-priviledge" and stealthing and how that could, theoretically, give specific transgender men conditional male privilege in specific social aspects, is that everyone who is talking about it has never, in their life, had to be stealth for their safety in all aspects of their life because they are white and American/European.
I'm big enough to concede that yes, if we're ignoring race, class, weight, ability, etc, other intersections of oppression, a perisex trans man who can pass flawlessly as a cisgender man and is stealth, as in not publicly identifying as transgender, could achieve, in specific social areas, something akin to male privilege. But, what he would gain in that social position of privilege, he loses in being able to access his own community for support and gains a whole new set of problems. He loses access to the trans community, and often the LGBT community in general, because he is "cis".
This whole hypothetical male privileged passing stealth trans man hyperfocus reeks of " if I add enough privileges to a hypothetical individual who is oppressed in only one verticey, the one we are specifically talking about, I can force you to be cruel to them and basically make their oppression null and void by forcing you to acknowledge this hyper specific theoretical individual. This totally isn't a stupid attempt to drown you in contingencies and unrelated social/systemic privileges that has nothing to do with both the topic at hand and the experiences of 99% of the rest of that community!". That's not how oppression works. No shit we can say the perisex rich thin white cishet able minded man with a physical disability has access to privileges but that doesn't erase, at the end of the day, he may die because he is medically neglected due to be disabled in some capacity.
His new problems as a stealth trans man? A constant state of surveillance. Anyone could out him as transgender. Any mistake could out him as transgender. A stray travestigation could end his life. Every old and new family member is a liability, every old and new friend is a liability, every new/existing/potential/ex partner is a liability, every doctor is a liability (even if he's post-op!! Phalloplasties look great but they will, regardless, look different from a naturally occuring penis and balls). Every moment is lived in a constant state of paranoia that, at any moment, everything in his life could come crashing down. I also feel the need, that if we are comparing the experiences of a stealth cis-passing trans woman to a stealth cis-passing trans man, even though she will experience mysogny and he will likely not, both of them will still have access to cis privilege so neither are truly going to escape accessing some form of privilege.
What I feel like this entire hypothetical about a privileged trans man whose passing and stealth and post op is missing is that most individuals who are stealth, aren't stealth because they want to be but because they HAVE to be. For some reason Transandrophobes think that trans men stealth so they can access male privilege and that's just horse shit. Stealthing is rarely a choice as much as it is an act of survival. Sure, there are stealthing white trans people in the US and Europe who could be openly trans safely but just choose not to but they are a tiny minority. Most stealth trans folks aren't safe being trans so they have to make a choice:
A. Remain suffering in the closet because they don't have the money to pass. (No new clothes, no haircuts, no hormones, no surgeries, no documentation changes and no money to ditch town and start a new life where people won't know you)
B. Be openly trans and hope for the best, even if you don't pass. (Often resulting in anything from assualt, rape, forced marriage, forced pregnancies, murder, take your pick)
Or C. Try to stealth and hope you pass enough to trick everyone. (Living your life in constant paranoia that anyone could figure out you're trans and that everyone in your life that you love and loves you could hate you at a moments notice. If not abandon you... If not beat, rape or kill you.)
So please, while you are waxing theory around this hypothetical trans man that makes up less than 5% of the transmasc community with conditional access to some mild form of male privilege, remember that he sits under a sword that could fall on him at any time for any reason that you will never have to sit under if you aren't stealthing or live, even if only mostly, in a trans safe or neutral community. Forced stealthing and the closet can be equally damaging to an individual and just because you don't experience that, doesn't mean it is a privilege. Most trans men are not stealthing, most trans men (and trans people in general) do not pass in every single aspect of their lives. Stop trying to apply the minor benefit this one type of trans man could access to the experiences of thousands to millions of trans men who will never access it because they could never stealth. Male privilege is only given to those that society acknowledges as cisgender perisex men, if a trans man doesn't fully pass and is openly transgender, he will never see that privilege.
How about we focus on the experiences of the 99-95% of the transmasc community's experiences when we talk about overarching theory that applies to all transmascs instead of the purely theoretical privilege of a small group of trans men that is already flimsy at best? I care about their experiences too but I'm not disingenuously saying they describe the entire fucking transmasc community like y'all are.