You've identified two issues here -- one has nothing to do with the other:
1. Abusive, pretentious behavior on the part of a passenger and
2. Reasonable discussion of UA's ups and downs, highlights and lowlights and, more generally, it's ability to meet customary standards of customer service and provide a passenger experience that is competitive with other airlines.
I don't think there are many folks who participate in this forum who epitomize (1) above. Far more common is the sort of dialgoue described in number (2).
Personally, I am always very polite and even deferential in my contacts with United people and I don't consider it the end of the world if I don't get an upgrade or some other such nonsense. I do this because it's the right way to act and because I find that the old cliche about catching more flies with honey especially holds true in the airline industry. Still, I reserve the right to disagree with UA on certain topics and express my opinions to them directly and on FlyerTalk, but always in a respectful manner.
As I said, one has nothing to do with the other.
[This message has been edited by smg77 (edited 06-18-2001).]