People bond around problem solving and creative tendencies. You'll notice that people who are really intense, really "into it" are much more comfortable talking about their work or subjects that are close to their work or the endeavors which are closest to them.
Language binds. If you can't get into the language, if you can't respond to it, and produce it yourself, you're out. If you want to get in with people, you have to talk the talk, and walk the walk, as the cliche goes. It is unfortunate, but a human tendency nonetheless, one that can lead to xenophobia at the more extreme ends.
Openness seems to come with security, and things close as insecurity rises, which is an obvious enough association I suppose.
