I wrote a thing about why I believe the best and most useful decentralized applications are going to be the ones that utilize multiple protocols. I imagine a world where ActivityPub, Dat, and Secure ScuttleButt are all seen as tools in a toolbox rather than as ecosystems, and what kind of amazing software we could build with them outside of the central/corporate paradigm.
https://blog.datproject.org/2019/03/22/three-protocols-and-a-future-of-the-decentralized-internet/