I’ve pondered this too OP. GC women are accused of “hating trans people” and I honestly do not think that is my motivation at all - I’m GC because I care about women and children and I think gender ideology is harming them. I don’t think trans people should be persecuted or harmed for being trans.
But, I do feel distaste and annoyance with the concept of someone announcing they’re trans, and I’ve tried to ask myself why.
I think what it is that it is actually human nature to distrust and even stigmatise someone who pretends to be something they are not. Deceit and dishonesty are not good for social cohesion and we have an instinctive “alarm bell” reaction. In any other context I think that’s normal and widely agreed on - eg someone pretending to have a professional ability or qualification they don’t have, lying that they have cancer, impersonating a security guard and so on. Likewise we don’t condone people saying they have a disability when they don’t, an ethnicity or age they don’t have, etc.
It’s then even worse that this ideology not only requires everyone else to accept that people “are” something they are not, but demands they overtly agree and affirm it. It’s a deep insult to our instinctive reaction to falsehoods. I think allies and supporters of the ideology feel this too, which is why they are so vocal and vehement - they are trying to suppress this feeling on the assumption it’s just their privilege and innate bigotry making them feel that and they must do better.
Then because of this whole situation being as it is, ID-ing as trans does appeal to a lot of narcissistic and controlling people and predatory men. I can’t understand why anyone would deny that - it’s so obvious that if we condone demanding other people agree you are what you say you are, and taking another group’s rights and access to their spaces on that basis, a whole bunch of people with other motives are going to run with that. So we get used to seeing a glut of cases where trans is clearly linked to fetish, grifting or plain old criminality and that association can lead to a scepticism.
And lastly, to me, anyone who IDs as trans is by definition sexist AF. They can only possibly think someone has a “gender identity” that doesn’t “match their sex at birth” if they they think there is such a thing as a gender identity that DOES match your sex. That’s sexist and I am not on board with sexism and don’t like sexists.
That is not to say real dysphoria about the sexed body doesn’t exist - and I sympathise with and care about people who are suffering with that - but the answer is support and help to accept yourself as you are.
Do I hate trans people or want them genocided - no. Does “coming out as trans” make me think you’re a roaring sexist and more likely than average to be untrustworthy, controlling or predatory, especially if you’re male - yes and with good, statistical reason.