The heart of the problem is body language.
It's an actual language that must be learned and spoken, but a lot of people for some reason never learned it, or learned it poorly.
When these people interact with strangers, it's exactly like the guy with a bad understanding of a foreign language who tries to speak it, and instead of saying "Hi, are you friendly? Lets be friends!" he says "Hi, I want swallow your head!"
I hope you can see why people wouldn't like someone who goes around talking like that on a regular basis, and that the problem really does lie with the speaker, not the people he's speaking to.
What's worse, if he doesn't understand what others are trying to tell him (in the language he speaks poorly - aka body language) when he makes these kinds of statements he certainly can remain oblivious to the problem and be unable to fix it himself. If a person in that situation never meets a kind soul willing to help him speak correctly then he really is screwed, and there isn't much he can do about it unless he recognizes the problem on his own and seeks help.
What kind of help? If you don't speak a language, you can buy a grammar, or ask native speakers to think up some examples and build rules from them. Whereas if you ask people "How do I know if someone is bored?" they don't give you actual tips, or even "There's no rule, you have to learn it case-by-case" and a few examples. They just say "Oh, I can never tell either" when they obviously can, or "Well, they just look and act bored...".
One of the lessons highlighted in the thread "Less Wrong NYC: Case Study of a Successful Rationalist Chapter" is Gender ratio matters.
There have recently been a number of articles addressing one social skills issue that might be affecting this, from the perspective of a geeky/sciencefiction community with similar attributes to LessWrong, and I want to link to these, not just so the people potentially causing problems get to read them, but also so everyone else knows the resource is there and has a name for the problem, which may facilitate wider discussion and make it easier for others to know when to point towards the resources those who would benefit by them.
However before I do, in the light of RedRobot's comment in the "Of Gender and Rationality" thread, I'd like to echo a sentiment from one of the articles, that people exhibiting this behaviour may be of any gender and may victimise upon any gender. And so, while it may be correlated with a particular gender, it is the behaviour that should be focused upon, and turning this thread into bashing of one gender (or defensiveness against perceived bashing) would be unhelpful.
Ok, disclaimers out of the way, here are the links:
Some of those raise deeper issues about rape culture and audience as enabler, but the TLDR summary is:
EDITED TO ADD:
Despite the way some of the links are framed as being addressed to creepers, this post is aimed at least as much at the community as a whole, intended to trigger a discussion on how the community should best go about handling such a problem once identified, with the TLDR being "set of restraints to place on someone who is burning the commons", rather that a complete description that guarantees that anyone who doesn't meet it isn't creepy. (Thank you to jsteinhardt for clearly verbalising the misinterpretation - for discussion see his reply to this post)