It's a good question.
The idea of being gender conforming is an odd one because it implies that the "genders" available to conform to are limited to male and female, which are of course not genders.
There's a debate to be had about "non binary", because there is one school of thought that says that being non binary is being gender non conforming because you are choosing not to conform to either "male" or "female", but also another school of thought that says that non binary is just a new gender which has been invented and so people who identify as non binary are choosing to conform to that instead.
But if we assume there are only two genders to conform to, what the hell does that even mean?
Who determines what gender conformity looks like?
If features of being a gender conforming woman include things like having long hair, wearing dresses, wearing makeup and so on, does a gender conforming woman become gender non conforming at night when she takes off her makeup and changes into her pyjamas?
Does a Scottish man who usually wears jeans become gender non conforming at weddings when he wears a kilt? Or is he gender conforming still because a kilt is a skirt for men? If kilts are skirts for men and other skirts are for women, does a woman who wears a tartan kilt become gender non conforming? What if she happens to be a teenage girl attending a girls' school where a tartan kilt is part of the uniform?
Basically none of it makes any sense because it kind of implies that there is only one way to present as a man or a woman, without specifying what that way is, and it doesn't address whether someone is gender conforming or gender non conforming if they, you know, change their clothes.
Tomorrow I will work from home wearing jeans and one of my husband's jumpers, with my hair tied up in a ponytail and no makeup on. In the evening I will pick my kids up from crèche, remove my husband's jumper and use the secret opening in my otherwise very unremarkable looking T-shirt to breastfeed my baby. (Is this plain black T-shirt which is clearly designed to be worn specifically by a breastfeeding woman gender conforming or gender non conforming? If it is only for women, why is it not pink?) When I have finished doing that I will put a dress and makeup on and go out for my friend's birthday drinks.
Will I be gender conforming or gender non conforming? Or both in the same day? What happens the next day when I wear different clothes?
It's all just fucking nonsense isn't it.