I once heard the position taken by the Lib/Lab/Green panellists described as "luxury beliefs" - i.e. beliefs that confer status on the well-off or otherwise insulated while having serious consequences for the 'lower orders'.
In this case the places and situations in which women's rights and trans rights come into sharpest conflict are ones in which the panelists are unlikely ever to find themselves so they are privileged enough to not see or care about the effect their position will have on other less fortunate.
They and theirs are not like to end up in prison, or a refuge centre, or be competing for sports scholarships or sponsorship for example, so why should they make their own lives more difficult by going against the grain and engaging their brains in the service of vulnerable and voiceless women (as well as trans people) when noone who matters is going to thank you for it? No, no, better to see which way the wind is blowing, side with the biggest bully currently in the playground and not think too deeply about it all. Receive your pats on the back and enjoy a job well done.
For me it's the fact that they have the barefaced cheek to take this approach while simultaneously setting themselves up as morally superior representatives of the oppressed. It's contemptible.