in her email, Kelley suggested that the BBC article would end up being ‘transphobic’ because it represented trans women as ‘sexual predators’, which was a ‘central anti-trans argument’.
This in itself is very interesting and disturbing framing.
What she is saying is that certain arguments, irrespective of their factual truth or validity, should not be allowed if they are used by "the other side". The people with the bad ideas.
This is a really dangerous thing to accept, even when we think the other side is wrong. Take for example some of the genetic racists, who will point to statistics on black underachievement in academic tests. The fact is, that these statistics are true and no one really has a clear explanation as to why. So of course they are used by people who want to claim some races are genetically inferior.
But there are those who don't want to talk about these facts at all simply because they fear their use by such people, and who try and use rather unconvincing arguments about things like implicit bias to gloss over the information. This is a bad thing - it not only means the underlying problems aren't addressed, it ends up lending credence to the racists. Because people can see they are the only ones who seem to be looking at the information.
It's not a good outcome and it's very typical of identity politics groups like Stonewall.