No doubt, some of the self-moderating policies limit subjects of controversial topics. But it also filters out a lot of the routine reflexive debating that accomplishes nothing.
I'm surprised at some of the headlines that make it to the popular page. Not sure what to do about this. Maybe it can't be completely automated. Maybe there has to be some amount of manual curating of stories.
Forums like this tend to produce "Accepted" solutions that are argued blindly for. I certainly mean dogma.