I think true trans women exist
I think you mean that there are ways for men to pretend to be women that don't hurt women.
For example if they are gay they won't be looking at women in a sexual way in changing rooms or if they pass we wont know they are there. If we call some women it doesnt mean we have to include abusive men in the definition of woman.
This behaviour does harm women because it takes single sex spaces away from us, and what it is to be a woman.
A young gay man might be a victim of this ideology, but it isnt womens role to walk them through it, or to humour them until they see sense, if they ever do. The idea that women are everyone's mother, and men are children needing care is gender.
We cant say that some men are vulnerable to trans ideology, yet treat these men as if they are women, or different to any other man. Thats saying trans ideology is dangerous, but we are going to support it anyway.