I've often made contrarian arguments, and at times pessimistic ones. Not about people's individual undertakings, as that would be against what I consider the spirit of things here, but in a 'general case', I think it's perfectly healthy.

The catch 22 is that if everyone agreed and if everyone came here for one type of discussion, then it would not be diverse and interesting. If everyone here had shared the same points of view, things would get boring quick.

It is one of the first facts about teams... dynamic and diverse teams have a higher probability of success, I would think that could apply to a discussion based community.