Yeah that might contribute (idk if it's the only thing contributing to the way these discussions go) , an idea I had was that you can downvote by spending your upvote generated points.
Note that this is just one of the ideas implemented in Slashcode, which for all its faults was and still is probably the most sophisticated discussion forum software on the internet.
I agree it's not the only thing contributing, but this would be a great place to experiment with those kinds of changes.