I might be biased in my perspective because I tend to focus on links that make it to the front page. It's true that many links end up languishing in obscurity.
I just think the level of effort involved is different. For instance, the person who posted the link to the study we're now discussing earned 199 points with far less effort than you put into replying to my comment. Many of the links posted are copied from Reddit, Twitter, Slashdot, etc.
I am sure what he actually got is much less than that number. If you got 200 up votes to a comment then that's 200 karma, but with submissions it is different, maybe dang can shed some light on that. Also what gets traction depends on a lot of things that you will find that most people will have the vast majority of their submissions have little to zero activity. So it is not that easy, some will manage to do it but the purpose is to limit that to something manageable. Then I think dang is managing both up voting ans down voting rings. With up voting being harder (everyone can do that)
I just think the level of effort involved is different. For instance, the person who posted the link to the study we're now discussing earned 199 points with far less effort than you put into replying to my comment. Many of the links posted are copied from Reddit, Twitter, Slashdot, etc.