JKR doesn’t believe trans women deserve rights that normal people have, and believes that they are inherently threatening to women just by existing.
She wrote a book series about how your bloodline doesn’t define who you are as a person, and then turned around and decided that the sex organs you’re born with determine your propensity for criminality.
For some reason she scapegoats a group of people representing less than 1% of the population for crime against women and it doesn’t make any statistical or logical sense to those of us who haven’t been living in a moldy flat sleeping on a bed of cash.