By Mathew Goldstein
My understanding is as follows: A female, a.k.a. a biological women, produces the larger and less mobile gamates. A male, a.k.a. a biological man, produces the smaller and more mobile gametes. Biological sex can usually be determined genetically. An analysis of chromosomes predicts which type of gamate a person produces close to, yet maybe slightly less than, 100% of the time.
People who are trans women are often, but not always, producers of male gamates, and vice versa for trans men. This renders them distinct from women who produce female gamates and men who produce male gamates. The production of gamates varies over time, but such chronological, age based, variations do not change the fact that most (but not all) trans people produce (or have produced, or will produce, or have the biological machinery to produce) the gamate type that defines their biological sex to be, at least partially, different from their self-identified gender.
People, including trans people, usually experience puberty with either a male or a female hormone profile. Those two profiles are usually identifiably distinct. These two different puberty hormone profiles usually result in two identifiably distinct sets of physical changes which tend to be long lasting absent medical or surgical intervention.
There are relevant questions that appear to currently be difficult to properly answer without more information. To what extent, and how quickly or slowly, do the physical changes of puberty dissipate or reverse when trans people are subsequently given hormone treatments to match their preferred gender when their gender identity conflicts with their puberty? Do trans people given hormone treatments before or during puberty fare better or worse overall than those given hormone treatments after puberty? Are minors sufficiently knowledgeable and independent to opt to medically or surgically alter themselves without a substantial risk they will subsequently regret their decision? To what extent is the participation of trans women in various athletic activities that are restricted to women (because men have a substantial performance advantage) undermining the opportunity for non trans biological women to win those athletic competitions?
We can then proceed with identifying the negative facts that are antithetical to human flourishing, and what we can and should do to promote human welfare by countering those negative facts. So, for example, if the available evidence favors the conclusion that people who identify as trans gender benefit from being socially accepted with the gender they identify themselves as, then we should do that. If the available evidence favors the conclusion that various medical or surgical interventions to facilitate better matching of physical traits with gender identification are beneficial for trans gender people then we should do that. If the available evidence favors the conclusion that trans women who experienced male puberty retain similar advantages to biological men in some athletic competitions then we should favor such trans women competing with biological men in those athletic competitions. Etc.
Meanwhile, let’s not prioritize fixed conclusions over the evidence, or prematurely commit to conclusions lacking sufficient supporting evidence. It takes time and effort to collect and evaluate the evidence covering a variety of different possible better-versus-worse practice alternatives that only recently became widely available technically as a result of new medical and surgical capabilities. We should defer to the consensus of disinterested experts (people whose material well being is not changed from the results and who seek out and evaluate the relevant evidence). The evidence, even after it was obtained and evaluated, may sometimes fail to provide us with clear policy guidance. There can be trade offs without a single alternative or particular set of alternatives representing best practice. We should be willing to recognize and accept that outcome also.
Sabine Hossenfelder has commentary on her Backreaction blog Trans women in sports: Is this fair? Her article is good, but we sometimes disagree. Her conclusion is that fairness in sports competitions is illusive (in an absoluteness sense) and therefore the entertainment function has priority. I think the less fair a competition is the less entertaining it becomes insofar as the entertainment value is not sadistic, which is one of the reasons why an asterisk is placed next to the athletic achievement history of top athletes who are subsequently revealed to have taken performance enhancing drugs. She says that there is no problem when the hormone treatments began before puberty. While there may be no significant problem with that in the sports competition context, for a child who transitioned early there potentially can be life long negative side effects (such as an inability to produce offspring). She acknowledges the distinction between transgender changes associated with empirically identifiable medical conditions related to biological sex and those that are not related to such a condition, but she does not view this distinction as having good practice relevance. In contrast I think this distinction could be relevant for determining when transitioning qualifies as good practice, particularly with regard to children. She says males do not have a substantial endurance advantage. Females are better able to utilize fat stores for energy and conserve glycogen which provides them the advantage in 100 mile (and more) jogs. However, she omits mentioning that males have a larger aerobic capacity (VO2 in eighties versus low seventies for females) which gives them the advantage in marathon distance runs.