No, this is not a mere worldview phenomenon. Apparently the NYC LW group has successfully proved, contrary to all stereotypes, that rationality done right makes you a more attractive mate.

Contrast:

1) "How could you say that! You terrible mean person who wants to hurt my feelings!"

2) "You need to understand that when you say something like that, it makes me feel as though you're trying to hurt my feelings, whether or not you do."

3) "I'm sorry about how I reacted; even though I know on the level of rational probabilities that it's extremely unlikely you meant to hurt my feelings, I'm still working on getting my brain to alieve that and not just believe it."

Let's say you've got a mate at level 1. Then you join a group in which you find (a) single people at level 3 and (b) a widespread understanding of the concept of the "sunk cost fallacy" and the importance of saying oops and changing your policies occasionally.

What do you think happens next?

And yes, NYC LW is demonstrating that this also works with women realizing that they can no longer stand to be around non-rationalist guys.

PS: Cultish countercultishness. I'm actually pretty sick of hearing someone yell "Cult!" every time rationalists try to coordinate as well as a model railroad club. Why Our Kind Can't Cooperate.