Perhaps KB watches a lot of Kardashians, and has taken to heart Caitlyn Jenner’s observation that the hardest thing about being a woman is figuring out what to wear? 
The most instructive aspect of KB’s ongoing public commentary on issues related to gender identity/trans rights is that she herself has tweeted things that are wildly transphobic. And yet she has not (so far) been called on it by those who routinely bully Joan MacAlpine, Joanna Cherry, Ruth McGuire, Jenny Marra, Rosie Duffield, Johan Lamont, et al.
For example, consider KB’s tweet - which she still hasn’t taken down - asking why women should have any input in GRA reform. Obviously, regardless of one’s views on whether, when, and how “trans women are women” it’s incontrovertible that some trans people are women. Is she implying that trans people are some third (or possibly third and fourth) sex; neither women nor men? It’s reminiscent of the Samoan Prime Minister who claimed that, for purposes of competing in sport, people should be divided into “men, women, trans, and tomboys."
One might almost intuit that transphobia, or ignorance about trans people, or saying things in the public sphere that hurt and dehumanise trans people as a group are OK with this cabal. As long as you support certain political projects - the ones that subsume and give away women’s rights, erode safeguarding, and foster a climate of rape apologism - anything else is just acceptable collateral damage.
No reasonable person thinks an MP is going to be completely up to speed on all issues all the time. There’s no need for KB to wade into this debate at all if she’s not willing and able to keep herself informed. Plenty of KB's SNP MP and MSP colleagues (including, thank goodness, my own MP and constituency MSP) keep scrupulously silent. Nevertheless, she persists. Why?