obunta

What do you mean by "the behavior of the other sex"?

Surely it's only reproductive behavior that is actually sex-specific? For females that would be pregnancy, gestation, birth, and so on. For males, ejaculating semen.

Other behaviors can be performed by either sex, wouldn't you agree? So when someone says they are "non binary" because they don't perform some extreme of femininity or masculinity, based on whatever cultural sex stereotypes they've been exposed to, they are one amongst billions of other individuals who also don't do that, aren't they?

I think we may be talking past each other. How does what you're saying relate to the "non binary" concept?

Adherence to cultural sex stereotypes is a spectrum, isn't it? Within the context mentioned by the other commenter, that's what "non binary" refers to: not behaving in an entirely feminine or masculine manner.

It doesn't really make any sense as a distinguishing concept anyway, as pretty much the entire human population is "non binary".

The "gender binary" itself is just cultural sex stereotyping, so pretty much everyone is "non-binary" in practice. As almost no-one behaves as the caricature of femininity or masculinity that some people have unfortunately come to believe represents women and men.

So it's not really a useful concept at all, and certainly not as an indication of mental disorder.