"No Woman would do that!"
They mean well, they really do.
Natal women, that is. Or more accurately, some natal women, when faced with a trans woman friend, family member or acquaintance.
They think they're helping you escape some unimaginable faux pas of either clothing or appearance. Sometimes they're right in that a little of the bloke has shone through, mostly though it's simply a shorthand for "I wouldn't do that!".
'Cos here's the thing: women are not an army of clones, they dress and behave in a huge diversity of ways. So the chances are that whatever the behaviour or look, many women do it.
It's indicative of an acceptance crisis in the mind of the originator, by saying that no woman would do what you are doing they are in effect saying that you are not a woman. Fair enough, it they've known the scruffy bloke for a decade that's a tough ask for some people. Give it time. And I don't need to be told I'll never be a natal woman, I have the lived experience to prove it. But the upsetting thing isn't that. Instead it's the suspension of the normal rules of commenting on female appearance.
Consider this, your friend asks whether her bum looks big in that skirt. Do you say "It's nice, but maybe the other one has the edge", or do you tell the truth and say "Your bum looks like a continental shelf and your legs look like tree trunks, make it go away!". Of course you say the former. Gently passing comment on appearance disasters is something all women have hard-coded, the latter is definitely something no woman would say to another.
Perhaps "No Woman would say that!" is an appropriate response.