"...in need of treatment..." - What's the most effective treatment option for gender dysphoria? Hint: the answer is social / medical transition and social acceptance of their gender identity. We have extensive data showing as much, and that's supported by every major medical organisation. One of the many problems with saying that being trans is a "mental illness", is that you're just exposing yourself to be a horrible person, by trying to deny mentally ill people the most effective treatment option, and instead treating them like vile monsters.

@NotThatGuy When you say "most effective treatment", what do you mean? Do you mean the treatment that has the result that trans people most prefer? Conservatives reject the idea that the preferences of trans people should trump all other considerations. They often present the analogy of someone who thinks they're Napoleon. Such a person would prefer that we pretend that they are Napoleon, but does that mean we are obligated to do so? As for your last sentence, you present no basis for that at all.

@Acccumulation In medicine, effectiveness of treatment is measured by the well-being of the patient. Someone thinking they're Napoleon is a bad analogy because that entails false beliefs (but even in those cases, we don't treat such people like monsters nor try to legislate them out of existence, like conservatives do with trans people). Trans people don't have false beliefs (no matter how much conservatives try to insist otherwise) - the very source of the distress of many, and why they require treatment (transition), is because they're painfully aware of the reality of their body.

@NotThatGuy "Someone thinking they're Napoleon is a bad analogy because that entails false beliefs" Not if we redefine "Napoleon" to mean "person who identifies as Napoleon". "(but even in those cases, we don't treat such people like monsters nor try to legislate them out of existence, like conservatives do with trans people)" I am discussing one particular point, and you're trying to change the subject to the entirety of conservative conduct.

"Trans people don't have false beliefs" A lot of them do. Abby Thorne has straight up said that it's an ontological truth that trans people are what they say they are. At best, they assert statements that are false given well-established meanings of words, and taking their statement as not being false requires redefining words.

"Just about the only "other considerations" conservatives can conjure up is either fear-mongering about things they think might happen," That's just nonsense. Conservatives don't want to refer to trans women as women. They don't want them in women's bathrooms or in women's sports. Those are all things that are real.

@Acccumulation "Not if we redefine..." - no, it's still a bad analogy. You don't understand what being trans means, and you don't seem interested in trying to understand. So that leads to you making disanalogous analogies. "Trans people don't have false beliefs - A lot of them do" - that's a lie (or egregious cherry-picking) based on your misunderstanding of what being trans means. And yes, "lie", because you're lying when you interpret what others say according to your own definitions, despite very clear signs that they use other definitions. You're just skirting around semantics.

@Acccumulation "Conservatives don't want..." - that is one of the most telling parts of what you said. Conservatives want, conservatives don't want. It's not based on science (trans people have that). It's not based on statistics (trans people have that). It's not based on legitimate concerns of well-being (trans people have that). All conservatives really have, is their own preferences for people fitting into some boxes that many people don't fit into, and they have that preference because of any number of bad reasons (e.g. being raised into it or unjustified religious beliefs).