I know the difference, I just think it's retarded. They're basically the same thing, only one is reality, the other is wishful thinking.
It's not me doing the dehumanizing. It's them dehumanizing themselves by not accepting how they were born.
They can exist for all I care, but I'm not gonna move my life around to suit their needs.
But it's as much an illness as, for example, schizophrenia is. As much as people would want to declassify it as one, it's not magically gonna not be one now.
For example, gender dysphoria is a symptom of said illness, because during it, they may become a danger to others or themselves, just like when schizophrenics feel stuff, that is not actually around, and that might make them violent towards themselves or others.
Just going along with it doesn't work, because even if they finally think they've done enough to actually pass as the other gender, some person may, maliciously or not misgender them(because some people might not truly know and then accidentally misgender someone), which makes them spiral into madness, making them scream what pronouns they wanna be called, and/or harm themselves later because now they genuinely think despite all the work, trying to change themselves to suit other gender, they still don't look like that among general populace. That cannot be healed with affirming everything, or just forcing everyone to "be nice". And that's just for the ones who ACTUALLY try to change. I've seen men, who have a full fucking beard, and have done nothing at all, calling themselves trans women (and losing their bearded shit when referred to as men), and I just cannot take this shit seriously ngl.