There's an employee at my local Wawa who's misgendered me repeatedly, but I don't believe it was malicious; I'd just shaved in preparation of top surgery, which wasn't doing me any favors, and I'm a pretty flamboyant guy.
At the same time, if I'd had my full beard and was dressed in stereotypically masculine clothing (instead of androgynous pajamas), I'd have been pretty offended. In the same vein, I can't fathom why that woman was misgendered at all, much less repeatedly; if it was as blatantly malicious as she says it was, I can understand her explosive reaction. I don't necessarily agree with it, but I understand it.
I hope, for all the people using it to defame her and the rest of the community, that her speaking out about what actually happened helps. At least now, instead of cisgender people only seeing the "crazy transgender woman," they can see the truth, too. Some will ignore it, but others will learn from it—I just hope there's enough learning to make a difference.