I think it would hugely affect interaction. The point about everyone wanting to be accepted is where we would see the real issue maybe more so than now. People going through rough periods in their lives (likely teenagers but not exclusively) who don't feel accepted or are not comfortable in their changing bodies and long to be accepted could be bullied even more so and felt even more alienated.

A group of bullies going through all of someones submissions and down voting everything could be tramatising to some. Maybe if they had it so that you could down vote linked articles only, but even then when a group of bullies downvotes everything someone links to, the individual will question themselves and their interests.