Obviously broader than the scope of this conversation, but let's not forget that /society/ is bad at this. You carve out a subsection of the larger culture, and, surprise! Sexism is still a problem. I find it absurd that anyone would think the larger tech community /wouldn't/ have this problem.
Thus, I'm pretty happy that, fex, the Node community seems to have a decent grip on keeping things under control, at least in the early days. There will be occasional trolls, newcomers, and people that don't "get it" yet, but I think the community leaders are leading responsibly.
You're right that it's not about the language of choice. But a community is made of people. I think that the Node community's niceness has little to do with JavaScript, and more to do with the fact that there were folks like you, mikeal, maxogden, nexxy, polotek, ryah, substack, janl, etc, who imprinted the community with your sense of values and a culture of kindness early on.
But keeping that ball rolling, as the community gets bigger, is very challenging, and it does stress me out a bit. It takes such a little match to set the whole thing on fire!
So I think as long as the Node community remains aware of the gender issues and goes to lengths to promote a friendly and tolerant environment that's the key. But to put it in perspective, I think that everyone should be doing that no matter your language of choice. :)