Arch -- I'm sorry, but I didn't really understand your complaint. The author was using words that are verbs, including gender.
Fatigue and exhaust are verbs. Debates over nomenclature fatigue and exhaust me. I can fatigue a metal rod by bending it back and forth. I can exhaust my supply of dish soap. I can accomplish great things even as I age. I can refine my taste in Italian wine by [i/]educating[/i] myself. I can honor the request of my neighbors that I not play loud music at night.
However handed and cultured are typically used (in the senses presented) as verbs only to create past participle, since the act of creating mirror asymmetry (becoming handed) and familiarizing oneself with high culture (begining cultured) are virtually never done explicitly in any way that need describing, so we need only the past participle. (Of course, we hand over our keys and culture bacteria on a petri dish.) Similarly, the implicit process of becoming gendered rarely needs a present tense (in terms intransitive sense of developing a personal gender identity, rather than the transitive sense of discerning and construing somebody else's), and neither does transgender.
Gender is not an adjective. It is a noun, or, at times, a verb. So why should the neologism transgender be one? We speak about gender studies, but here we are using the noun gender as an adjective, as we when we talk about the business section of a newspaper or a law school at a university. Business and law are certainly not adjectives! We wouldn't ever use transgender in the stand-alone sense as a noun that we use gender, but that's because gender does the job. We might talk about a person whose transgender status means that their gender falls outside of the binary conventions. Similarly, we don't need the verb transgender because it is included in the verb gender as it describes how a person's gender identity forms. But the past participle is quite useful: A person becomes gendered through development from a fetus through adult, and sometimes they become transgendered when that development falls outside societal norms.
Sarah, we don't say transsexualed because there is no possible sense in which sexual could ever be a verb; however sex can be a verb (in the same sense as gender) so transsexed makes sense, even if it is rare.
Virginia,
I much, much, much prefer trans people. Trans is an adjective, short for transgendered or transsexual, depending on the context, just as bi is an abbreviation for bisexual. We sometimes say spokeswoman or Irishman, but these construction are either titles (as with a job) or antiquated ways of describing nationality. The second sense is the one that comes across in transperson, since being trans is not (I hope) a profession. And it's kind of dehumanizing: I'm a person first, and when you call me a transperson it gives me the sense that being trans makes me less of a person, one that needs qualification.
That's also why I don't like transsexual (or white or black or any other adjective used to describe people) used as a noun meaning transsexual, (or white or black) people. It is dehumanizing, and ought to be used sparingly.