is there there’s a shock that would come with a change from what you’ve lived, and that being cisgendered wouldn’t negate that shock, it would be miserable, but I don’t feel an attachment in the sense that I feel glad I was born a man.

I'm having a hard time making sense of what you are trying to communicate, particularly about a shock 🤔 You should know it's not uncommon for cis people to not have thought about their gender or to have particular attachments to their assigned gender. Usually people just haven't thought about it and have no awareness of all the ways they are attached to their gender.

Still, most men have some attachments, they usually would say they might be unhappy if their penis and testes were lost in an accident, for example. And most men would probably feel unhappy having to wear dresses and so on. All you have to do is imagine or actually attempt to live as the opposite sex and you'll quickly get a sense of what aspects of your gender are important to you.

That’s what I meant when saying if I had been born a woman I wouldn’t be happy with the idea of changing to be a man.

If you were born a cis woman you would be happy being as a woman, but the question is whether you, as you are now, were born into a woman's body and then given a girl's name, and then expected to have tea parties with your girlfriends and do braiding circles and so on. Your parents would send you to school in dresses and expect someday you would get pregnant and marry a man, and so on. It's really hard for cis people to actually consider what this would be like, I don't really hold this against you, it's genuinely difficult (maybe impossible, that's my current view - lived experience and qualia just can't be transferred).

But I don’t think it’s fair to reduce all mental illnesses to being not biological and being “solved with therapy or anti-depressants”, I think that is part of the stigma against them.

I don't mean to communicate that all mental illnesses are addressed that way, just that some mental illnesses are addressed that way, and as a result a common line of reasoning is that gender dysphoria should be treated that way too. This isn't the argument you're making, but I'm raising it because this is a relevant point in the discussion about gender dysphoria as a mental illness and you're not the only person reading these comments.

Physical treatments are often more helpful than those things, different illnesses need to be addressed in different ways, not treated as a generic umbrella for characteristics society doesn’t approve of.

I agree with this.

Sorry for not addressing all of it but I’m skeptical that you read what I wrote there because I explicitly spoke in favor of gender-affirming care as the treatment and your response reads to me like I was arguing against it.

I did read what you wrote, but people don't always have awareness of their views or the consequences of their views.

I think you might be missing that the trans person you're talking to is sensitive to a conservative anti-trans talking point being raised and argued for, and that merely disclaiming the common conclusion the anti-trans point is designed to reach does not completely address this. I'm not going to answer narrowly by ignoring that larger context, that would be irresponsible.