@stillathing
How about ending all endemic violence regardless of who commits it?
Part of tackling a problem, understanding its causes and allocating resources involves identifying and naming the problem. The specific problem I am speaking of is violence committed by humans born male (90% of violent crimes, 98% sexual crimes - hence the use of the word endemic). Obscuring language definitions and data, whether for benign or malicious intent, will not help solve this problem.
Ostracising an entire group for the terrible acts of a tiny minority - why can't we all agree that is wrong?
Firstly when you take into account the huge range of sex based intimidation and crimes, the woeful conviction rates, the fact misogyny is not a hate crime, and the fact many, many women don't report (due to awful treatment in court, fear of not being believed / further attack and an internalised sense of shame) I am not convinced the minority of men that commit crimes against women or harass women is actually "tiny". That said most of us here continue relations with male colleagues, friends and relatives.
Secondly either you support sex segregation for some provisions and services or you don't. There is copious data to suggest it is both needed and wanted. Safeguarding works by looking at the features of the "tiny minority" and putting procedures in place to stop others with similar features doing the same. Exclusion, or "ostracising" can be a part of that.
Thirdly both view points are seeking to "ostracise" - one wants to "ostracise" trans boys from girl guides, the other trans girls.
Fourthly (is that a word?) when there is a huge systemic power imbalance, such as there is between makes and females, having a single sex environment can be good for reasons other than just safety. Think about what message girl guides are sending out by declaring themselves single gender rather than sex. The gender stereotypes for girls can be incredibly regressive and harmful. How would a girl who does not fit them feel about that, how would a gay girl feel about that or indeed a girl who is currently identifying as a trans boy or one of many other identities? It changes the ethos of guiding. Maybe that is ok, for there to be an organisation which is for the gender identity of girl. But we need to be honest about what that means.