Many feminists intensely dislike "transgenders" and in my opinion for good reasons. Transgender is NOT the same as transsexual.
Transgender is for some or most claiming to be and acting transgendered is nothing more than being a cross-dresser in public. It is 100% sexifying and stereotyping women as being nothing more than makeup, wardrobe and hair style. There is no "wear lipstick and a skirt" gene or otherwise being born desiring to shave your legs.
For whatever reason it is, transgender is wanting the stereotypical social definition of being a woman - no different than if a white person prefers the culture of a black community so dyes his skin dark demanding people call him an African-American. Yet that man isn't African-American, did not grow up as an African-American and most African-Americans definitely would NOT accept that he's really black.
Transsexual is not about social stereotyping, but instead to literally be a female. Nearly all transsexuals will also be transgender, while most transgender will not be and do not want to be true transsexual. A true transsexual will always want - desperately want - sex reassignment surgery (SRS). A transgender does not need SRS because this is not necessary to play the social stereotypical act of looking female in stereotypical ways.
Noting the distinction between transgender and transsexual, is a person born "transgender?" No. No one is born genetically pre-disposed to wear high heel shoes, a bra and a skirt. Those are all popular social gender stereotyping that constantly change. Transgenders are, by definition, "sexists."
I do believe it is accurate, but rare, that a small number of people may be born "transsexual," where their dna does not match their internal sense of what sex (biological sex) the person is.
I have no problem if a man wants to put makeup, a dress and the other social stereotypical appearances as a female - socially or privately - and an act they want to play socially or as a sexual fetish. Same visa versa for a woman wanting to play-act being a woman. However, it is extreme sexism and if that person then claims to REALLY be a woman it is EXTREMELY demeaning and degrading to women.
That is why, personally, I do not accept that a "he" has become a "she" without SRS as a matter of the person's sex. I person may play any social stereotypical social role they want to - including being a man socially pretending to be a woman - provided the government does not require everyone to accept that sexifying and stereotyping of what a female is as a matter of law.
If a person has SRS surgery, then and only then in my opinion has a "he" become a "she." This is not because I have anything against transgenders/cross-dressers. It is because I refuse to trivialize. marginalize and sexify what being a female is. I can fully accept and respect a transsexuals claim of being the opposite of their real sex if the person has SRS surgery.