To the contrary, I believe that people's gender is usually extremely important to them. What I find less important is having to specify their gender whenever I'm talking about them just because of language constructs. In English it isn't actually that bad, since it's limited to using correct pronouns; but in some other languages I have to be careful to not misgender anyone pretty much whenever I talk about them or to them - regardless of whether their gender is relevant to what I'm saying or not.

So I'm only a grammatical gender abolitionist :) I don't see the point of gendering people when I talk about them unless I talk specifically about their gender. As a happy side effect, this would also massively reduce the risk of accidentally misgendering someone.