It can come off as aggressive, for sure. I do think a healthy community needs skepticism and introspection to remain that way.
But I do think people unintentionally reinforce the notion of the status quo needs to be reinforced/destroyed, which can affect the types of thoughts you'd think about sharing with a group.
Yes... there are times I do just say fuck it and post it anyway. HNKarma is pretty worthless after all. :)
But more to the point, and the reason I hope this is tongue in cheek, I hope nobody here actually optimizes for or cares about a "HN Karma score in the bazillions." Last I checked you can't cash in HN Karma for a fiat $$$ check or happiness. There's a bigger world out there, folks.