There's a fantastic book about this written by Julia Serrano called 'Whipping Girl' [2] that goes over these things and more and describes these phenomena as 'Transmisogyny' - trans individuals being subject to both misogyny and misandry depending on the situation, and sometimes both when it's convenient.
[1] - https://freedomforallamericans.org/legislative-tracker/anti-...
[2] - https://www.amazon.com/Whipping-Girl-Transsexual-Scapegoatin...
https://juliaserano.medium.com/debunking-trans-women-are-not...
Have you ever characterized something which you don't necessarily agree with, but appears genuine and well argued, as "reasonable"?
Her words. I read it. In the essay Rowling says explicitly that she doesn't think trans women should be allowed to use women's bathrooms or women's shelters, dismisses concerns about suicide rates in the trans community, and lumps in advocates for trans rights with Donald Trump and incels as part of a new wave of anti-feminist sentiment sweeping the liberal west.
I didn't find it well argued or reasonable, it's a rehashing of tired arguments that transphobic people have been making on Mumsnet and Fox News in the US for years.
Where does Chimamanda advocate for discrimination against trans women? Because there is nothing in your source that implies that.
Also, that is only a motte in liberal circles. Saying "I have and will continue to stand up for the rights of transgender people" is not necessarily a no-brainer moral stance for the general population.