I was introduced to Steemit two months ago because I work with one of the code contributors. I didn't adopt early quite frankly because I didn't think it would take off. I miscalculated the alure of easy-money to users and I thought that the idea was there but the interest was not. I'm happy to see this site skyrocket, but I also know that the general population hasn't even heard of Steemit yet. I'm not sure that they ever will, and let me explain why.
This site is separated into two classes.
The early-early adopters were able to get into Steem early, and either curate content or buy steem power for very cheap and build up the own influence on the site. They are the whales in this situation and their votes can influence a post greatly. I have seen a post go down $100 in value just from one vote. These people are in the background of the site, and they have the power to greatly censor the content of the site through their votes. If you are a whale, you have whale friends who can bump up the value of your content as well.
The other class is those who have joined recently, whether it be for fame, fortune, or just to tell their story. Even though their content can be better than the whales, they have visibility issues with their posts because of their lack of voting power. They don't have any whale friends, and therefore their posts will only gain a modest amount of money until if they're lucky, a whale upvotes them and they become a bit more influencial.
100 plebians can all upvote a single beautiful post, but if a whale disagrees with it, that value is gone.
The only way to ensure the longevity of this social media platform is through change, but I doubt that this will happen because what whale would want change when they're already at the top.