A fundamental distinction needs to be made between blockchain-based and non-blockchain-based decentralized services. Blockchains are insanely ambitious, century-scale, state-killing, finance-replacing behemoths. WE DON'T NEED ANY OF THAT STUFF TO REPLACE FACEBOOK! You're exploding the problem way out of scope, and constant focus on blockchains seems almost like a false flag to demotivize people who just want to build decentralized alternatives to Facebook, which is already an astoundingly huge problem.
Stop trying to put blockchains in web decentralized systems. They're not going to work for several more decades. All we need to do to kill Facebook is solve the self-hosting P2P UX problem, and create a W3C-like body that allows developers to participate in standards creation process for how we schematize common social data. That's it. Once everyone is running a federated node in the cloud or in their basement, then you can go back to doing blockchain stuff.
Stop trying to put blockchains in web decentralized systems. They're not going to work for several more decades. All we need to do to kill Facebook is solve the self-hosting P2P UX problem, and create a W3C-like body that allows developers to participate in standards creation process for how we schematize common social data. That's it. Once everyone is running a federated node in the cloud or in their basement, then you can go back to doing blockchain stuff.