I haven't seen the speech. Sounds like I missed a treat. However:
Anybody can make a slip of the tongue in the heat of the moment. The reaction of those around her, though, from the sound of it, should have alerted her to what she'd actually said and she should have corrected herself. As a privately educated former medical student she should know this stuff.
She's 37. It wasn't compulsory to study biology when I was at school. It is now, and has been for a long time. There is no question that KB must have studied biology long enough to learn the basics of genetics. I did Biology O level in 1977. We covered XX/XY chromosomes as part of the reproduction and genetics topic and it wasn't cutting edge stuff even then. I thought it was common, general knowledge, but I see from this thread that it isn't. It is, however, really basic stuff if you've studied enough science to get into medical school.
Putting all of that to one side, though, you'd have to be really, really stupid not to grasp that human beings, just like other animals, have always been able to tell which members of our species are sexually mature males and which are sexually mature females, and the reason we can do this is obvious - it's essential for the survival of our species that we know who to reproduce with. We can do it from one quick glimpse of someone walking most of the time, and the clincher is if you find out that another human has given birth, guess what! She's a female. Only females conceive, go through pregnancy and give birth. Not all females do those things, but no males ever, ever, ever give birth. Nor do they menstruate, nor do they breastfeed, nor do they go through menopause. These are the common experiences of female humans, and no male will ever share them.
It's therefore totally mysterious what a male means when he says he identifies as a woman. What's he identifying with, given he can't share the biology? How is it not dependent on transient cultural stereotypes?
This ability to correctly sex other members of the species is so super basic that almost everybody in the world can do it from babyhood. Nowadays, however, a few people in rich countries have managed to unlearn it, and have convinced themselves that biological sex is too complicated for anyone to understand, so they won't even try, and all the people who say they do understand it are either lying or are just too stupid and poorly educated to grasp that it's too complicated for most boring ordinary mortals to understand.
I hope KB loses her seat at the next election. She doesn't appear to have the basic common sense and judgement to be in Parliament voting on complex issues. Her electorate deserves better.