Not that you don't already know this, but. I really think the logic here goes back to people's inability to understand gender outside of a cissexist gender binary.
These people aren't thinking, "trans men get male privilege even pre-transition, even non-passing, even when everyone around them perceives them as women"
They're thinking, "if we admit trans men don't get male privilege in all situations, then the opposite must be true of trans women, and that would be transmisogynistic".
They're remembering years of (generally correct and useful) frameworks that exist to deconstruct transmisogynistic/TERF arguments, and because they don't fully understand these frameworks- and oftentimes, the people who created them didn't think through the underlying logic either- they can't actually think deeply enough about them to understand them in the context of new information.
These arguments were not designed with trans men in mind, and when confronted with the experiences of trans men, they tend to feel the arguments themselves are being threatened.
These arguments have been around for a while, and I suspect a lot of people know them already; but for the sake of being thorough, here are a few:
TERF Argument: "Trans women were raised as men, which means they were taught to think and act the way men do, and therefore continue to think and act like men all their lives."
Counterargument: "Trans women can't be socialized the same way cis men do, because as women, they will understand those messages to be for someone else, and internalize messages intended for women instead."
TERF Argument: "Trans women will always be Biological Males, which means they will never have to deal with problems like abortion access, stigmatization of periods, and other reproductive rights issues. This means they are privileged as cis men."
Counterargument: "Being a woman means you are always subject to misogyny, no matter what, and it is bigoted to say that trans women are not women. Even if trans women don't need access to abortion, neither do many cis women; besides, this is made up for in all the other ways transmisogyny impacts them. They do not suffer less on the whole."
TERF Argument: "Trans women can't experience (what we consider to be) misogyny, therefore they can't ever truly relate to cis women, therefore they can never be Real Women."
Counterargument: "Trans women are perceived and treated the same way cis women are; their transness didn't take away from that, it just adds more, different oppression on top of it."
The problem with these counterarguments is that they meet the TERFs where they are. They don't challenge their foundational logic- they just argue that trans women fit into that logic as women rather than men. And because they fail to examine transness as anything but a more misunderstood, but otherwise indistinguishable copy of cisness, the gender essentialism and binaristic thinking are still incorporated into this logic.
This leaves us with a few transphobic implications:
Trans people do not share experiences with cis people of their AGAB; sharing experiences with your AGAB means you are not actually the gender you say you are.
Trans people are perceived and treated as their actual gender. Their transness is mistreated, but this is wholly separate from their gender.
But these implications can be ignored or skated over, so long as the original ideas are never put into a context that includes trans men's experiences. So people fight to keep trans men's experiences out of the conversation, and come up with arguments like:
"Trans men don't experience misogyny, because they aren't women."
"Trans men are not relevant in conversations about abortion and other reproductive rights issues, because they are not women and are not targeted by misogyny (If we do include them, it is "as women")."
"Trans men are effectively socialized, perceived, and treated as men, and are therefore exactly as privileged and dangerous as cis men."
"It is invalidating to suggest that trans men experience anything a woman does, or that trans men might ever be perceived as a woman, because that would make them women."
"Trans men experience oppression for being trans (transphobia), but this is wholly separate from their gender/AGAB."
"TERFs validate trans men's experiences with misogyny as an extension of considering them women, and as a way of invalidating trans women's experiences with misogyny. Therefore it is intently TERFy to say trans men experience misogyny."
("What the hell is a nonbinary person")
These are designed for the purpose of keeping us out of the conversation, both with the altruistic- but misguided- goal of preserving the only arguments against TERFs they know of, and because they don't really believe that including trans men in the conversation is important in the first place (we're men, after all, so why should they?)
This is already long, but. For the sake of being thorough- again- I wanna also talk about what happens when you argue these same TERF talking points while including trans men's experiences; as well as nonbinary experiences, which are generally left out of the conversation altogether (with the exception of these people sometimes saying "transmasc" and "transfem").
There is no singular, universal "male" or "female" socialization, and trans people, having an incredibly complex relationship to gender in the first place, will often have an even more complex relationship to gendered messaging. Applying this idea to cis people is already dicey at best; applying it to trans people is fully nonsensical.
All trans people are, or can be, subject to misogyny. Reproductive healthcare is only one aspect of a much larger system that impacts us all in different ways. The total amount of misogyny one faces from others also has nothing to do with anyone's actual gender, and everything to do with how they are perceived in various contexts, or what sorts of needs they have as an individual. This also has nothing to do with what makes anyone a woman.
The oppression one experiences does not determine their identity; nor does one's identity determine what their experiences with oppression are/will be. There are patterns, commonalities, and certainly systems built with the goal of harming a particular group of people- but it isn't always that simple in practice. Most trans people will be perceived as both a cis women and a cis man at some point or another.
If someone knows you're trans, you likely won't be treated the way cis men or women are, regardless of gender or presentation. Trans people are generally treated as whatever gendered class (man, woman, or trans/"other") is most convenient to the cis person in that moment; oftentimes multiple at once.
Anyway. I know that wasn't really the point of the original post; it was just a very good jumping-off point, and well-worded to help me bring some thoughts together.
