GC: What is wrong with trans people working in sexual violence prevention?

In my view, nothing. I don't think that persons should be automatically excluded from working in sexual violence prevention or recovery programs solely because they have a (certain) gender identity - or solely because they don't have a gender identity, either. Or because they eschew gender identity ideology altogether. Whether a person is qualified and the best fit for a job in sexual violence prevention or recovery/therapy depends on a plethora of factors that all must be considered both separately and in totality.

However, one of the factors I think is crucially important in sexual violence prevention and therapy is a candidate's sex. Some positions are best suited for female candidates, some for males.

But even in situations where sex is of paramount importance, I believe that reserving a position for a person of one sex or the other, or favoring a candidate due to his/her sex, needs to be done carefully and judiciously in a legitimate, proportional way. Not every female person is naturally suited to this work, and not every male is inherently unsuited.

Also, I believe that people with gender identities at odds with their sex - be they trans, non-binary, gender-fluid, ace, whatever - need services that take into account their own situations, and that when seeking help and education they should be able to find providers with whom they feel most comfortable and at ease.

What I am leery of, and I object to, is the idea that people do and can only feel comfortable with, and only can be helped by, others who are carbon copies of themselves and who ascribe to all the exact same ideologies and views.

However, one thing that gives me concern in regards to the particular question you've raised, OP, is the fact that so many people who have gender identities and are wedded to gender ideology are squeamish about sex, in denial of sex and its consequences, uninformed about sex, clueless the about physical differences between the two sexes, and likely to try to gloss over the differences between males' and females' experience of sexual violence and its consequences for the two sexes. IMO, people who can't discuss and deal with sex, and get distressed by mention of the very word sex, are not suited to be working in the field of sexual violence in any capacity.

My own impression is that only some people with special personality traits, training and skills are suited to taking positions as policy makers, program designers, program operators, counselors, therapists, educators, etc in areas like sexual violence prevention, recovery and investigation. Most of the population - no matter what our sex, age, sexual orientation, gender identity, gender presentation, religion, race, ethnicity, nationality, culture, political beliefs, class background, current socioeconomic status, reproductive/parenthood status, etc - are simply not cut out for this kind of work.