well, I don't see it that way. I'm sorry they took their toys and went home, and maybe am part of the reason why, but I think it's more a case where they didn't like to reap what they sowed.
There were often cases where a real position was being put forth, but it was rarely defended if 'attacked' (rebutted) -- that's where everything else flows from. That's why there was another category proposed, it seems to me, one where squabbling could take place without overwhelming threads where the OnT stuff would be a real discussion. Squabbling can be fun, but why expose everyone to it?
and I way don't agree with your characterizations of liberals as respectful, or, really (though you didn't say it) of being rational and analytical. Both sides of many arguments show a lot of symmetry there. For every pro-gun nut on the right, there's an anti-vaxxer on the left. Liberals may be more interested in why someone wants their guns, but really aren't going to accept their rationale as legitimate. That's fine, it's just how we all are. Personally, I think Jonathan Haidt had the right idea -- you're liberal because of the things you intrinsically value, or conservative. Do you respect authority more than you care about fairness? Evangelicals are conservative for that reason, for example. That's as simple and fairly accurate dividing line as any I know of.