The great majority of transitioning trans people do not regret their decision to live as their true gender.
It is interesting to see how transphobic, lesbian, "radical feminists" (TERFs) use the exact same arguments that were used to invalidate and marginalize lesbians.
The most common one was that homosexuality was an acquired sexual perversion caused by the propaganda of the homosexual movement. If you could protect children from the gay movement, there would not be any lesbians.
This is obviously the same argument that is used today to stop lesbians from adopting children. Lesbian parenting is unnatural, will hurt the children and make them gay and so on and so forth.
The desistance-argument forms the foundation of the TERF argument against the the identity of transgender people. Since so many gender variant people, in the end, do not chose to transition, the TERFs assume that none of them are really of the gender they claim to be. They have been duped by trans activists.
This is a completely misleading reading of the research available, as it mixes up gender nonconformity with gender identity.
Variation in gender expression is used as a way of exploring both identity and sexuality among straight, gay and queer people. You will find “butch”, “femme” and “androgynous” people among all of them.
The majority of these people are not gender dysphoric. They do not experience a severe misalignment between their gender identity and their assigned gender, or between mind and body. They simply express masculinity, femininity or any other aspect of cultural gender in a way that feels right for them.