Oh good lord. I've just had a look at that mumsnet transphobia account.
Taking screenshots of comments on here that most people would consider entirely rational, and holding them up as an example of transphobia is going to backfire.
You only have to look at the BTL comments on any national newspaper to see how the ordinary person in the street thinks the whole thing is ridiculous.
Granted, it's a little irritating that the numerous 'oh no, not more of this. For gods sake stop shoving it down our throats' comments don't fully grasp the implications.
But saying that stating biology is transphobic, is absolutely going to ignite the touchpaper with the general public, who are already fed up with hearing about it.