Lord, I'm not advocating starting a mob to hound her employers to force her to apologise or be sacked, for no-one to ever publish her work again.
I'm saying if you unintentionally hurt someone, and you can see legitimacy in why they are hurt, you apologise to them. That is what I do. Surely that is just what normal, decent people do?
Of course, if she 'wrote what she meant' and understood how it would be received and does not care, she should not apologise. But from my point of view, and many others, including the person it was about, it was a crappily toned and quite cruel article. And if she can in retrospect see that, and feels bad about it, she should apologise. That would just be the decent thing to do.
I hope we can still live in a world where most of us can see the difference between terrorising people into abasing themselves with insincere apologies and those who genuinely see they got something wrong, feel bad about it, and say 'I'm sorry'.