The whole idea of the Decentralization movement is just that - a decentralization of power, finances, opinions, networks, businesses etc. A fracturing of large, hegemonic players in markets, to smaller, less influential ones.

Thus, I am assuming that plenty more platforms are going to fill more niche areas of Social Media, with different demographics depending on many different variables. Although it would be sweet for Steemit to be the "next facebook" - the allure would wear off as it would be too influential at disseminating information. It is my hope that decentralization will make it impossible to control large societal narratives like they are today.