First, it's essential to understand that nobody can actually change sex, and we need to stop pretending otherwise. Our sex is expressed in every cell, every strand of DNA, in our proteins, our organs, our systems, our physiology, our hormonal balances, our metabolism, our psychology, our emotional expression, and our behavior. Amputating healthy tissues such as penises, testicles or breasts does not alter our sex. Neither do hormone treatments. At best it's delusional to believe otherwise - at worst it's criminal deception and medical fraud. And there is no scientific debate about this whatsoever, in spite of the ideological assertions of the transactivists.
The difficulty here is that people without sufficient biological education keep trying to conflate biological sex with gender identity and they are not the same. Nor can we conflate gender identity with orientation, as orientation relies specifically on biological sex, and gender identity does not.
As I have posted before - without exception - if you have the SRY gene and active androgen receptors you will be male. If you do not have the SRY gene and you have inactive androgen receptors you will be female. Either one of those conditions biologically orients the entire human physiology onto a specific developmental pathway from fertilization to adulthood, and that will produce either sperm or ova. There are no exceptions to this. Every human was and is a product of an egg and a sperm.
If those four expressions of two characteristics screw up in our genetics then we have all of the Disorders of Sexual Development (DSD) and there are about 40 of those. Every one is a DSD of either the male or the female. Typically, those with a DSD are sterile.
Unlike sex, which is a physical reality anchored in biology, gender is a set of trivial characteristics associated with the performance of masculine or feminine behaviors. These are entirely cultural constructs and are widely varied from culture to culture across time. Typically gender is the box constructed to limit the power of females. Gender has no physical reality - there is no science for gender. It only exists as mental abstractions expressed in language. Only sex is real.
You can take every single behavioral association of masculine and feminine as defined by "gender" and depending on time and culture, we can reverse it completely: long hair is masculine - nope it's feminine. Only women wear skirts. Nope, only men do. Only women wear make up. Nope, only men do. And so on ad infinitum.
There are only two sexes for humans, three orientations, and 7.7 billion gender performance variations that are individual and unique expressions of personality. Beyond that, nobody should care what anybody's gender expression is, and that means making feminine boys safe from male violence, and masculine girls and lesbians safe from male violence (e.g. - straight men claiming to be lesbians under the trans flag). It also means that women and girls have a right to safe spaces where males are not permitted - not even trans-identified males.
This isn't something as simple and mundane as a mere disagreement or somebody's opinion. This is about the denial of the material reality of biological sex opposed to an extremely dangerous ideology driven by a well-understood psychiatric pathology. There is no middle ground here. You either stand with the reality of biology or you stand with a crippling set of delusions and their co-morbidities (anxiety, depression, self-harm and suicidal ideation, and identity disturbances). There is no possibility of compromise between those two positions. There's no such thing as a valid gender identity because gender is entirely a fictional social construct.
People people with personality and character disorders need help. Pretending their delusions are real does not help - it just makes their disorder worse. You might as well offer an anorexic liposuction.
The irony is that the accusations about the transphobia foolishness are rapidly breaking down as the real world begins to take notice.