I've been watching this on X for the past couple of hours. At the moment there are a lot of people complaining that "a GC author got a trans ally fired" (paraphrasing for brevity).
There are also people pointing out that the author didn't get anyone fired. Waterstones fired someone, presumably for being in breach of their social media policy.
What seems odd to me is that she has been fired for this. It seems more of a slapped wrist/apologise/don't do it again type of issue. So there is presumably something else going on - i.e. was she already on a final warning? Was there something about her response when Waterstones raised the issue with her that made it more serious? Etc etc etc
I would be high and dry if I lost my job, and I am in no way celebrating this woman losing hers.
I do think that more people need to understand that (1) calling someone a bigot is now less likely to result in them losing their job if all they are doing is saying that sex exists (and if they do lose their job, they will probably win their tribunal), and, (2) harassing someone, online or otherwise, may result in losing your own job, even if you are a vocal trans ally.