You hit the nail on the head. There is not much science in the current literature. There are a lot of claims and hypotheses and, from some of the less conscientious social sciences and the less rigorous studies, a lot of attempts at explanations that border on the mystical, but there is a dearth of hard studies relative to other topics.
That is changing, but in a charged environment you have to tread carefully. Plus, any rigorous studies are going to take time, which doesn’t lead to an easy resolution.
I think sex and gender are more tightly coupled than people want to believe. If I see good, solid work to the contrary, I’ll change my mind.
I’m also suspicious of the claims of social and cultural influences. They are so nebulous that they can be massaged into an explanation of just about anything that cannot currently be reconciled because it is yet unknown. It’s a bit like practicing astrology.
Although the same applies to biological males, biological females have many functional differences at the genetic and cellular level that biological males simply do not have. They are not hormone dependent and the introduction or withdrawal of hormone treatment does not alter some of those cellular functions. We ARE different from each other in a number of important ways.
In the meantime, what to do? Well, we can stop with the New Agey stuff; it’s not helpful. And, we can stop castigating ciswomen for being able to detect what is, to them, obvious male physical traits in transwomen. We should also stop stretching reality and requiring non transpeople to buy into weirdness about woman penises and male menstruators. Nobody buys it except for the faithful.
In this regard, I think transwomen have the tougher road to hoe because ciswomen are far more perceptive about subtle cues than are men. A lot of men don’t even notice subtle cues, but women are disquieted by discordant inputs and they notice those cues more readily.
It makes sense from an evolutionary perspective that women have to be more careful about being alerted to things that don’t seem right since they are smaller, weaker, and slower and many times further physically hampered by pregnancy and tending to infants.
Gender dysphoria is a real thing, the only reasonably viable treatment we currently have involves altering the body, and we should treat people with kindness and courtesy as long as that consideration is reciprocated. Shutting down people who disagree is a hostile tactic and makes them understandably angry. Disagreement is not assault and it’s emotionally manipulative to pretend it is.
Ultimately, however, ciswomen and transwomen have little in common from a life perspective. They have few shared experiences gender-wise, as biology dictates many of our life experiences and our pivotal moments in development, so there is going to be tension and misunderstanding and mistrust, but we can reach some form of truce, even if it’s an uneasy one.