[earthboundkid]

No, but FB/Twitter promote people who are vain, etc. because they drive traffic.

In a system like Google Reader or FB/Twitter before algorithmic feeds, you just see what your friends post in roughly chronological order. It still has the problem that people like to post junk, but there's a natural limit on it. Algorithmic feeds however promote "hot" content, which is pretty much inevitably emotionally driven. There are a lot of possible fixes, such as rate limiters and manual review of high performing content, but they all come down to the same thing: don't let sheer virality be the driving metric. The best way to decouple virality is just to make advertising against algorithmic feeds illegal.