Consider prisons, for example. There have been many cases recently of male criminals being transferred to the female prison estate, on the basis of their self-declared so-called "female gender identity", who have then raped and in some cases impregnated women incarcerated with them.
It should be obvious that the same risk is not present from other female prisoners. Even if they happen to look very butch and/or hirsute. So keeping prisons single-sex is clearly a much better policy for incarcerated women.
Even for bathroom spaces, the prospect of laws that penalize males who decide to use female bathrooms is good news. This is because the threat of negative consequences for such behavior makes it much less likely that any such males will even bother trying, which means that women in general will not only be safer, but also can feel safer, because they know that any individuals encountered in these spaces are almost certainly female. Even if, like Buck Angel, they don't conform to feminine stereotypes.
This is false. Female inmates are raped by female inmates, and male inmates are raped by male inmates. This is a "rape in prison" problem, not a trans women problem. In fact, rape of biological women by trans women in prison is extremely rare.
And, again, your stated hypothesis is self-contradictory, because it implies that the problem of inmates getting raped is solved by putting trans women in male prisons, which is plainly false. It will likely increase the number of rapes.
"the prospect of laws that penalize males who decide to use female bathrooms is good news"
I remember tiredly accidentally using a women's bathroom after a long flight. I'm not looking forward to being punished for it because of the latest moral panic. I'm sure all of the women who are falsely accused of being men because they don't conform to societal stereotypes of what women look like also feel much safer.
Meanwhile, there are, as far as I can ascertain, currently no cases of trans women assaulting biological women in women's bathrooms. I'm sure cases exist, but they must be exceedingly rare.
There are, however, plenty of cases of trans women being assaulted (and, in some cases, murdered) in men's bathrooms.
This is why we have single-sex prisons in the first place, because of the inevitable harm to women, through violence, sexual assault, rape and unwanted pregnancy, that was committed against them by male prisoners in mixed-sex prison systems. Look up the work of Elizabeth Fry: she and other prison reformers extensively documented the horrors of prisons in Victorian England and in particular the awful impact upon women of being incarcerated with men.
Exactly the same is happening now, in the 21st century, because of these misogynistic "gender identity" policies that benefit males while deliberately ignoring the risks and harms inflicted upon women.
The truth is that most of the people currently stirring up a moral panic around gender are barely even aware of the existence of trans men and simply haven’t thought this through properly. Which isn’t surprising, as they don’t care about the issue itself, but only its potential as a political wedge.
This is not a reasonable assumption based on my experience talking to women, and if it was, I don't understand how it would work in reality. Even if biological women preferred sharing the women's bathroom with trans men, rather than trans women, how would biological women know whether they were sharing the bathroom with a trans man or a biological man?
It seems much easier for trans men to pass than for trans women, so allowing trans men into women's bathrooms basically ensures that all men can freely enter them, claiming to be trans men.
Any examples of this hypothetical situation actually happening?
If these spaces were regulated by law, and there was a realistic prospect of penalties for males who choose to impose themselves on female spaces, then this would have a significant deterrent effect. The males who say they're women (including males with a transwomen identity and your hypothetical set of males who claim to be transmen) would refrain from intruding.
I'll also leave this comment for thought. You're arguing that allowing transgender women into spaces reserved for women (unqualified) degrades the utility of them. I'm actually somewhat sympathetic to this argument, but not universally. I think allowing transgender women into women's sports is maybe not right, because transgender women don't have the same underlying physicality as women who have grown up with female hormones. I think it's an interesting discussion about why we perhaps somewhat arbitrarily segment sports in this way but not others (why no under 6 ft basketball leagues?) and the role that genetics plays in sports vs training and practice, but I think it's a generally effective means of allowing a group (generally women) to have meaningful leagues where it's not just women + men who aren't very good but have a genetic advantage. As well with regards to prison, since this is already a segment of the population (people in prison) who have committed some crime, so trusting them in the way we might trust random people from society to act may not be the right choice.
That said, your comments make it sound like you don't respect the existence of transgender people in general.
In particular, "I don't see how this is a self-contradictory position. Women who've decided to call themselves men are in fact still women.", and "It's a reasonable assumption that most women prefer to share female spaces with other women, regardless of how they look, and not with male intruders who have decided to disregard women's boundaries for their own pleasure while falsely identifying themselves as women.".
The first is I think clearly denying the right of someone to identify as transgender, and the latter is a fallacy. I agree that women would not want to share the bathroom with "male intruders who have decided to disregard women's boundaries for their own pleasure while falsely identifying themselves as women.", but this is not an accurate description of transgender women.
If you think it's an inaccurate description of how you feel (that you do in fact respect transgender people) I would suggest that being more careful in your debate might help you to convey your arguments effectively.
How is it not accurate? They are male (by definition), so when they decide to impose themselves upon a female space this means they are doing so with a disregard for women's boundaries.
Based on your comment, you seem to believe that "woman" is just an identity, that any male can choose to adopt if he desires so. If that is the case, why do you believe this?