Hmm, this sounds a bit naive. I'm struggling with this for my entire life, and only a certain amount of alcohol helps me to do chit chat. But after the chit chat I always regret some things I've said, the whole thing is just rubbish. I simply don't like it to be forced to talk shit. I'm quite certain it's not a learned skill, it is pretty default for the most stupid people around us.
Concluding that something is not a learned skill because it comes easy to some is illogical. Human upbringing consist of a lot of social interaction (at least when done right), it is only fair that some people actually get good at it.
Anyway, I should probably have disclaimed my first comment more loudly: it's anecdotal. For me smalltalk is absolutely a learned skill. I used to suck at it, now I can get by, and it took a lot of conscious effort on my part. YMMV
