People are separating sex and gender without realizing, whilst they're arguing the opposite, I'm just pointing it out.
Sometimes people here are equating the words 'gender' and 'sex' (as they once generally meant exactly the same thing), and sometimes they're talking about 'gender' more along the lines you are, as a role or set of expectations of one's sex. I think you're just not always aware what they're saying.
The gender critical folk are usually doing the latter in order to analyse the position of the gender activists and allies. I feel confident most GCs will agree that people should not feel societal pressure to fulfill an arbitrary gender role, just as you say we shouldn't.
The gender activists and allies are usually the only ones conflating those uses of the terms, switching as and when it suits, because they want to choose something they call their 'gender identity', but they hold the idea (overtly or more subtly), either that it's their actual sex or that their choice of gender should trump their sex in certain ways, like demanding to use the other toilet or, in at least one instance I remember, claiming they were discriminated against because they were refused gynecological services, despite being male without any reassignment surgery.
They range from the relatively sane, who know their sex but just want to behave and feel like the opposite (or none) to those who literally think their soul somehow got in the wrong body. Some therefore think of transition as moving towards the way they want to look, despite knowing their actual sex, while others are on a quest to fix the body that they think should never have been theirs, because they think their (inner, true) sex is right and their body is wrong.
In just about every account of 'transition' that I've read about, the person demonstrates that they thought they were 'trans' because of some gender role or stereotype. It may have been removed by now, but at one time the front page of the Mermaids uk website advertised the tremendous joy and freedom of a kid who 'came out as trans' and was on the path to medication and surgery. He was a boy, but at some point he knew he was a girl, it reported in his own words, because he never liked football like his other friends, and liked to hang about with the girls doing their sorts of games. Right in your face, there it was. The most regressive sexism, persuading kids they'd better get their body in line with their likes and dislikes.
/rant