Well, if the moderation is well decentralized, scams like that would be quickly taken care of.
Skillful, anonymous and randomly chosen moderators should be able to delete such things very quickly when rules are broken in well decentralized social media
What is you concept of a decentralized social media. Who will moderate the contents?
When you have a body who can alter the database without any instruction or they do not need to explain it to anyone, they will abuse. In the current structure of facebook they have people (moderators) who are legally bound to explain their jobs to their superior.