I think it runs deeper than simply the assumption of bad faith. When growing up children go through phases of conforming to their parents and then distancing from them, and also conforming to their peers and then distancing from (most of) them as well. This seems to be a part of the personality formation process - at some point people feel compelled to disagree in the most confrontational form (and even demean their opponents) not to look for truth, but to define their own self. They also often engage in group identity defining behaviors, such as rallies about persecution, "real men/hackers/programmers never/always do X" posturing etc. Also voting on agreement/disagreement axis (instead of useful/wasteful axis) is one of those. Incidentally, 18 yo is the typical drafting age for many draft armies, this is when "us vs them" mentality can be readily utilized.

What's remarkable is that with the advent of the Internet we have places where this process never ends. Rather than growing up, slashdot community is in perpetual adolescent disagreement mode. The most mature members are leaving and going elsewhere, to be supplanted by the newcomers.

I'm not necessarily right, but this narrative helps me make sense of what's going on and provides a perspective on the community dynamics.

The two questions that interest me now are:

1. Where are new HN members coming from?

2. Where are they going to when they leave?