I can only speak for myself, as each person has their own path. I will try to shed some light on your questions. I know for a cisgender person it is sometimes difficult to conceive of gender identity as being different from sex (genitalia). Many are only now coming to the realization that one's sexual orientation is not always congruent with one's gender identity and/or sex either.
Surgeries such as SRS (vaginoplasty) are not "mutilations", they are medically necessary surgeries to correct a genital birth defect in a person whose physical brain matches their gender identity. Transition is not a choice it is an imperative. it may be held at bay for a time, but when it is time, it is a matter of life as their true self or dying wearing the mask of someone they never were.
I know of no one who transitions to "become a woman or man". Transition is about bringing the physical body into congruence with the existing gender identity of the physical, natal, organic, biological, brain. Because gender identity is hardwired during our time in utero (unlike gender roles and gender expectations which are social constructs) we cannot change gender identity (just as we cannot change sexual orientation) because that would require a type of brain surgery that hasn't been developed. These people always were the gender identity they KNOW themselves to be.
Transition is not about "adorning" or "mannerisms". It is not done to fit in. Many who transition never feel they will fit in. It is about bringing to body into congruence to complete oneself. People don't transition to look good for someone else. Many people do get reconstructive surgeries for other conditions as well. Often their emotional well-being is crucial in that as much as the physical.
I don't see Joy or any other trans person as allowing the gender binary to define them. Gender Identity, Sexual Orientation, and Physical Sex each exist across a separate spectrum or continuum. Joy and others bring their bodies into congruence with their own selves. She and others of transsexual history are not transitioning to have their bodies conform to perceived gender covenants. Transition is for the person not the culture, society, or gender binary.
It isn't about names and dresses... it isn't about whether or not society accepts them. The clothes are worn because that is what others around them with the same presentation are wearing, there is no particular attachment to the clothes any more than a cis person would have for their favorite outfit. Even in a world of perfect acceptance of gender identity, a person of transsexual history would still have the need for congruence.
In closing, yes the surgery is risky as all surgery is, yes it is costly because it is an involved procedure and there are not that many specialists performing it. It is NOT unnecessary and it has been shown to be an overwhelming success both in physical aesthetics and in the physical, mental, and emotional well-being of the person.
Just my 2¢, but I hope that answers some of the questions.
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