It seems to me that gender nihilism is too much on the renunciation side of analysis. Sure gender has been constructed by power(though I also think there is a morphic resonance basis for it as well as is the case with all language. I'm really not a fan of construct reductionism)but so has everything else in language and culture.
Instead of using nihilism as this unchecked renunciation driven negation use it to cut the non preferential fat on a personal basis. For this reason egoism should precede nihilism. Gender is one of those things that some people like and some people don't. You don't have to bring demands or abolition to the table which are ironic words considering that they began in the alien realm of statecraft.
Make gender your own or disown it. Ownness and disownment not abolition, for gender, work and all the other spooks. A both-and approach needs to be taken with affirmation and negation to keep the spooky excesses of both in check. Nihilism on its own has been misused for over century now and I don't think it's a just a matter of bad thinkers misapplying it. Egoism as I see it is the contextual mediator of negation and affirmation for what I see fit be it gender or anything else.