We do it "That way" because doctors job's are to treat illnesses and to keep people alive. Doctor's have discovered that treating gender disphoria gets the best results (least deaths, better mental health outcomes).
This is categorically untrue. People who "transition" are actually more likely to commit suicide and more likely to have more mental health issues post "transition".
Here's the real issue:
Person for various reasons has extreme discomfort with the body they are born in. There's a high component of sexual abuse in the LGBTQ++ community in general. (Not everyone who identifies in this community; but the stats are pretty high.) There's a high degree of domestic violence in this community. (Again not everyone but stats do show higher rates of partner violence in homosexual couples.) Higher rates of depression, anxiety and suicidal ideations, attempts and "successful" suicides are also prevalent in LGBTQ++ populations.
And stats show that these psychological struggles remain high even in "LGBTQ++ friendly societies"!
Biological females who seek to pass as male, most have different psychological reasons for their gender dysphoria then biological males wishing to pass as female. One research stat I saw for sexual abuse in biological female trans individuals is close to 85%. That's really high. I think this is the highest of any subgroup in society. Interestingly though, the only stat I could find for biological males wishing to present as females, having been sexually abused as children was 17% (lower than the stat for homosexual men). This is an interesting stat when we get down into the prevailing psychological reasons for why biological males want to present as female.
The most recent stat for sexual abuse in the general population is 25% (1 in 4) of females before 18 years old have experienced some form of sexual violation. Some researchers say it's just as high for biological males (also prior to 18 years old); but others say stats for males is 14% (1 in 7) have been sexually abused as children.
Current stat for homosexual men having been sexually abused as children is 35%
Most recent stat I'd found for lesbians having been sexually abused as children is 50%
Highest risk of males being sexually assaulted is while in prison. 2nd is while in the military.
Highest risk of females being sexually assaulted (outside of something like being abducted or being a prisoner of war) is college campuses.
Now, biological females looking to present as male; the prevailing psychological reasons are generally related to body discomfort, body hatred, fear of men (or fear of continued sexual violence) coupled with a temperament / personality that isn't particularly conforming to society definitions of sex roles or meanings of "masculine" or "feminine".
For biological males wishing to pass as female though; the majority of their prevailing psychological reasons is a condition called autogynephilia. (They are sexually aroused by the thought of themselves as the perfect woman. Thus they seek surgery to turn themselves into their own ideal of "womanhood".) Autogynephilia in the psychological literature falls under "sexual fetish" category. Autogynephilia hasn't been formally studied since the late 80's but the last researcher who did research male to female transgenderism cited 90% of "late onset" male trans treatment seekers he classified as having autogynephilia. He was a psychologist who worked with these men in the 70's and 80's.
Next we have the category of prepubescent children with gender dysphoria. If left "alone" (though treated for things like depression, anxiety etc.) 85% of them, by the time they are 18, come to identify as their birth sex. This stat changes though when adults tell these children that they are really boys born in girls bodies or vice versa.
Now.... current gender dysphoria treatment model?
What is the real message when we tell people with gender dysphoria that they are "in the wrong body" and the only way to fix their psychological distress is to interfere with their natural biological / sexual development, make them life long customers of big pharma and charge them thousands of dollars to remove healthy body parts, effectively making them sterile and for the most part remove their natural ability to understand and experience what sex actually is. Transgender surgery does not produce sexually functional people.
Basically the message is:
"You are defective from conception." And the treatment being based in a lie that says "we can make you the opposite sex" will never psychologically square that circle. (In this treatment model; the patient can never psychologically reconcile their feelings with their binary biological reality.) And the result is that there is actually greater distress (more anxiety, more depression and more suicide attempts and completions) post transition than prior.
And that is bogus science! It violates the Hypocritic oath that says: "First do no harm."
(Certainly a "treatment option" that should never be offered to children!)
And now.... the lawsuits of people who were "transitioned" as children and teenagers have so hit the medical system in Europe that most of the rest of the world (outside the US and Canada) has already shut down the "gender clinics" for children.
Harvard tried sex change surgeries in the 60's and they were a dismal failure then! So much so that they stopped doing them; because the men (primarily middle aged biological males who were seeking the surgeries) were more distressed, more depressed and more likely to commit suicide than prior to the surgeries. (Same outcome we're seeing now!)
Transition surgeries do not change the psychological issues that caused the gender dysphoria to begin with!
Which, in the context of a Christian world view raises the "What would Jesus do" question!
The true theological answer is "Repent and believe the gospel" Although this certainly isn't a "simple" answer for people who've gone far down these roads into this deception. Of course coupled with all the psychological issues and traumatic life experiences that brought them there in the first place. To "turn from one's sin" in these contexts will require professional and compassionate counseling. Assistance that's rooted in truth and the message of mercy for wounded people who've been affected both by their own sin, as well as the sin of others.
He rules the universe; yet hears the humble cries; bringing comfort to the broken heart.
The power of His word can split the earth and sky; yet mend the lives that sin has torn apart!
Yes, repentance is a difficult process for most people. But when Christ said "pick up your cross and follow me"; the implication being: This will cost you something.