Yes and no. I used "subpar" in scare quotes to refer to what I think was implicit sentiment in your comment above. Personally, I don't find text subpar, just different - trading off additional information for more control and efficiency, as well as range.
As for being unable to find someone in my immediate vicinity, there are two issues here, both of which involves self-selection. First of all, people in my vicinity often are preoccupied with something else, whereas whoever signals his availability for conversation on-line is probably a safe bet to talk to.
Secondly, when you look for people in your vicinity, you sample the general population. When you interact on a forum like this one, you sample through a much smaller population of people particularly tuned to that forum's topic and style of discussion.
I don't mean to say here that people around me are inferior to those I meet online; on the contrary, there are conversations I prefer having with those next to me (often, not surprisingly, about topics related to local context). I find off-line and on-line forms to be different enough not to substitute for one another.
> But I don't think that its necessarily the best option or that we should think that the only people that you can talk to on any given topic are necessarily not people who are sitting right next to you - on the bus/train/plane/park bench/etc.
I agree. Though again, self-selection. I'm equally fine with talking about things with people on the bus or on the other side of the planet. But I'm having this conversation here with you, on HN, and not with my friends over beer, because it's Sunday night over here in my timezone; most of face-to-face conversations I could have have selected themselves out by going to sleep :).
> Or to turn it around, it would be so much better to live in a society where you could just strike up conversations with strangers and not be judged for superficial BS like crumbs on your face.
Oh I would so love to live in such a world! But that will require serious rewiring of both our societies and our own insecurities, which would be a change of much more profound (whether good or bad) consequences than mere smartphones.