I think the main problem here is not that people are harassing her. The main problem is the fact that it is possible for people to be harassed in this way. There are a number of things that the people around someone have to believe for that to be possible. Beliefs that I would say are simply
wrong.
My main belief here is: if you care about preventing the personal misery of people like Lena Chen and Kathy Sierra, you should not try to prevent this type of harassment with judicial or technical means. You should try to change the beliefs of people so this kind of harassment is simply not possible, which automatically results in this kind of harassment not being perpetrated (because it is pointless).
Here are some of the beliefs that are necessary ingredients for this kind of harassment to be possible:
* people are not adapted to living in a small world, where your actions can become known to, and commented on by, a vast amount of people. Given you are living in such a world, you should internalize the fact that it shouldn't matter one bit what a few random internet commentators say or think about you.
You happen to have drawn some attention and as a result not only the one lunatic in your direct environment has noticed you, but another hundred of the thousands of lunatics out there have noticed you and are vocal about that. But they are just random unknown people. They think you are a slut? Why do you care? More importantly and much more relevant to solving this: why do your friends care?
* so a reasonable concern is of course: what is the actual impact of the beliefs and statements of these unknown people on your direct environment? How many of the people you should reasonably care about have noticed? How many of those people seriously wonder whether these random people are right?
If they have noticed: people adjusted to this world wouldn't believe anything J. Random person says. They would ignore it as one set of implausible datapoints in the overload of information available these days. If anyone believes it: good to know, those people are not fit to be friends or colleagues. Someone thinks you're a slut because some random people on the internet are saying so? What kind of gullible numskull is that person? A person maladjusted to this small world.
* suppose some facts are undeniable. These are pictures of you naked. Why is that a problem? Having seen someone naked or having been seen naked should not change the way you behave towards each other. That's allowing yourself to be victimized by the puritanical standards that have become a strong factor in Western civilization over the past fifteen hundred years. If someone cares about it being possible to see you naked on the internet, then that person is at fault, not you.
* suppose some facts are really scandalous. Let's say it's evidence of a crime, but it was too long ago to prosecute. It still shouldn't matter. You aren't a few photographs or letters and anyone who believes otherwise is, again, not worth the air in his lungs. I don't care if you murdered someone thirty years ago: if you've been a decent person ever since and I have no reason to suppose you would commit such a transgression again, then I should assume you will be a decent person now.
So, tl;dr: the reason it is possible for people to be harassed in this way is because too many people care too much about opinions of random others, care too much about what other people do and commit the fundamental attribution error. Solve that and the problem goes away.