Well, here's some basic economics: People react to a changing economic environment. As soon as they realize that they can't make the money anymore which they made before because the whales keep the cash to themselves, they will go elsewhere. This reduces the value of being on Steemit in total, which could go down significantly and causes those 16-17 accounts to lose a lot of the value for their self-voting. This again will trigger them to react by for example voting small fish or by creating profitable bots and prepping those up with some of their SP. Some users will notice this and increase their activities again until a new equilibrium has been reached and - Pardon - the next Socialist comes around the corner and tries to save the world again.