It's interesting to me that peakingatthemoment said:

If a male alters their body and is able to pass to people as female they are going to exist in society being treated as a female in most ways

And now Fleurista has said:

If a male experiences the world being perceived by most everyone as a woman, why would they feel they have more in common with trans people rather than women?

To me, these statements illustrate a major difference between the self-concepts of males who "identify as" women/girls and those of us who actually are women/girls. There's a lot more to going through life as a female human being in a female body than just being perceived and treated in certain ways by others.

I honestly don't know anyone female who derives her own sense of her sex solely or mainly from how others perceive her. Even if a female person lives a totally cloistered and solitary life as a hermit or shut-in who never leaves the house, or she only leaves the house covered head to toe face and all in a full-body burka like in Afghanistan, or she looks very "butch" and thus often gets mistaken for a male person by others when out and about in the world, she will still inhabit a body that is distinctly female in the thousands of ways that make human female bodies very different to human male bodies. And in my observation, what inhabiting a distinctly, unmistakably female body feels like to her internally in her own flesh and blood down to the marrow of her bones will be the major source of information that she relies for her knowledge that she is a woman or girl.

I think if those who believe women's self-concepts of sex is entirely or mostly about the perceptions other people have about us actually spent time speaking to a broad cross section women about this, they'd find that women's sense of being female usually has as much or FAR MORE to do with the physical aspects of our bodies that we experience and feel in every fiber of our being internally rather than how other people who observe us from the outside see and treat us.

Yes, the ways other people see and treat us shape and inform our self-concepts. But it is only part of the story of our sense of ourselves and especially our sense of our sex. For many of us, how others see and treat us is actually only a small part of the story insofar as our sense of our own female sex is concerned.

For many of us, our sense of ourselves as girls and women comes largely or even mostly from the physical issues we start dealing with once we start getting periods - which the majority of females start at 11-12 - and breast development, which most girls start even earlier. PMDD, menstrual cramps, heavy bleeding and clotting, period blood leaking all over, pre-menstrual breast tenderness, ovulation twinges/pain, female urethral problems like recurrent cystitis, vaginal yeast overgrowth aka "infections" when under stress, our vulnerability to pregnancy and all the intense worries and dread that come with that, pregnancy, miscarriage, termination, childbirth, breastfeeding, ovarian cysts, fibroids, uteruses perforated by IUDs, a lifetime of breast cancer checks and worries about various kinds of lumps, menopause, osteoporosis, gynecological disease, hysterectomy, bones that are easier to break than male bones, skulls that make us more susceptible to concussion and TBIs than males are, muscles and reflexes that make us slower and less physically powerful than males, female grip strength, a far greater likelihood of experiencing autoimmune diseases and Alzheimer's, a far greater risk of suffering lower limb injuries than males due to doing sports and wearing high heels, etc - these are the kinds of embodied, "lived experiences" that most female human beings rely on for the knowledge we are girls and women.

Catcalls, being groped, being ignored, being sexually preyed upon, getting talked over, getting called "miss" and "ma'am," being mansplained to, being told to swallow your feelings, being passed over for promotion at work, having your ideas stolen from you and credited to someone else, having your health complaints dismissed by doctors, being told you don't matter, being called a slxt, whxre, Karen, pearl clutcher, fat cow, stupid breeder, ugly mxnhater, old bag, a witch and TERF and so on - those sorts of experiences are reminders that we are female, and that in our society females are seen as second-class and second-rate. But for most of us, those kinds of experiences are not where our basic knowledge that we are female comes from. Most of us get our fundamental sense of our selves as female human beings, as girls and women, from a lifetime of inhabiting female bodies every second of every day, year in and year out - not from how others see us and treat us. Nor even from what we ourselves see when we look in glass mirrors.

The embodied experience of being a female human being with female DNA, female cells, female organs, a female immune response and so on is fundamentally different to, and totally separate from, how other people perceive us and how they treat us. It's entirely different to gazing at our physical selves in looking glasses too. These are points which seem totally lost on those who believe that being a girl/woman is simply - and mainly, mostly, entirely - a matter of giving off a certain outward impressions and being viewed and treated by others in particular ways.