I don't think most people would deny that men who believe themselves to be women are different from men who don't, and that masculine men who put "she/her" in their twitter bios are different from crossdressing fetishists who are different from GNC men who are different from transsexuals etc. But you can say that for anything, really. Being different results in a different treatment. But whether society mistakes a man for a woman shouldn't suddenly make said man comparable to a woman. It would only make some of his experiences comparable to a woman. The fact that these people are still physically male and have years of male upbringing doesn't change. Now, can a man experience being treated as a woman by society in a limited capacity because he consistently makes them think he's female? Yes. That doesn't make him some kind of a woman, though, or his experiences comparable to actual women, and the staggering amount of misogynistic male trans people shows how little "living as a woman" affects male misogynistic views, biases and upbringing. Men speaking in the name of women is damaging to women, regardless of how these men identify or how much they claim they understand women. Think of all the men who wish they could be women so they could get easy sex. They cannot comprehend how this plays into the objectification that women are saddled with their entire lives, nor have they ever experienced the sexual difficulties that women have with their anatomy and patriarchal male-centric sex (which men ofc insist is all for the women's sake because ofc men know best what women want and need, despite straight men having the worst track record of satisfying their partners out of anyone 🤔). Even if said man turned into a woman, how would you explain to him that his interpretation is wrong and rooted in his male biases that make him glorify male systems that favour his sexuality and his supremacy? He would insist until he was blue in the face how good women have it sexually, despite evidence to the contrary being everywhere around him, even if he ignores everything women say (as men do).

The life of a man who wants to be a woman is entirely different from a woman. The experiences of the man are always going to be coloured by him being male and revolve around convincing himself that he is female as strongly as he possibly can for the sake of his well-being. This is something women, due to being women, do not experience. Like it isn't even on their radar, much like how it's not on one's radar to convince themselves they're a vertebrate or a human. Now, the patriarchy does make women feel distress and sells them the notion that, due to being female, they need to affirm themselves through damaging gender roles, but this is extremely harmful to women and results in a host of mental issues, anxieties and insecurities (which is by design - these are the traits that the patriarchy wants women to have so they have to be dependent on men for affirmation). What male trans people want is to be treated as women, but what women need is to be treated as human. These two motivations coupled with one's upbringing make for a very different and not particularly comparable life and mentality. By virtue of being male, male trans people are always going to approach life as a man who wants to be a woman, and their mental well-being is going to depend on how successfully they convince themselves of this. Meanwhile, the "cis" gender role that is so often thrown at women as a sign of their privilege is a form of oppression, chains that women need to break, not embrace. So even if they're both outwardly treated the same, the biases and life experiences they bring are going to colour their experiences.

My point is, the reason why we're against labelling men as women just because they "live as women" is that merely experiencing a part of your life being treated as a woman isn't the same as literally being female forever, from the moment you left the womb and couldn't even form a thought to even after you end up a skeleton, with no regards to your thoughts or feelings, be they of affirmation or hatred. And I just don't see any benefit to automatically labelling men who pass as having experiences comparable to women when so many male trans people are both misogynistic and very much male. Hell, the trans people who pass best tend to be especially misogynistic, because they tend to abuse all the patriarchal social cues that people almost instinctively associate with women, and frequently feed on their misogynistic male confidence and assumptions about women. I simply haven't seen any evidence that just "passing" makes a man less problematic than your usual man and as such I don't approve of labelling these men women in any capacity.