You don't really need Twitter, you need a platform and require the people that use the platform to bring in their ledgers so they are auditable by the public. I can view someone's work and examine if they're trustworthy or not. Similar to how people are signing their signatures, they could be just bringing together their ledger, which could be a bloom filter so it's just a single line of hash that I can verify I still own the thing they selled, you only need a system that can compare these and see if anything has been double spent. The point is, you don't need a running bitcoin-style blockchain for this. You can achieve the same validity with different means.