No, it's not becuase it wasn't even always like that until John Money came into the picture. Gender was always used for language and sometimes sex in relation to sex differences. So yes, they are the same thing and are always seen as such by normal people.

I fail to see why you are opposed to words that differentiate these two points

Look up John Money and see what this sicko did. That's why me and the majority reject this terminological distinction. I'm not supporting the works of a child abusing PEDOPHILE who took a term that wasn't even related to femininity and masculinity in the aspect of "societal expectations" (or people themselves in this manner) and bastardized it.

In your world, how do you even describe a masculine female or a feminine male? This distinction is crucial.

What I call them? Like everyone else. Normal people. At most, tomboy and tomgirl. Masculine women and feminine men. That simple. Not "GNC" queer/gender (identity) theory terms. I call them just I would call opposites but with different labels. Ex: feminine women, masculine men, androgynous women/men, etc.

Also, I'm not gonna sit here and be a hypocrite who bitches about TRAs when they try and change the definitions of woman/man and sexuality when people who do this whole "gender =/= sex" are doing the exact same thing. It's both or neither that get changed. The distinction is not "crucial." This line of logic is probably the fault since TRAs made their own form of gender definition using it.