Like some P2P kind of "Web of trust". Because it's more important to me what my immediate online environment considers trustworthy than anyone on the other side of the globe or people who I'd never follow to begin with.

There used to be a good approach called FOAF (Friend of a friend), which was pretty decentralized at the time, hosted on your own web server. Technically it was XML-based, but today it could be represented in a NIP or in JSON.

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