When it comes to belief and trust, generally trusted authorities are efficient, but create centralization. Web of trust solutions with no barriers to participation are decentralized but are susceptible to tampering or collusion. I think for Nostr there should be a machinist where a person earns trust with their locally community authorities (like mods) that then becomes verifiable and this transferable to other communities.
Here’s how a grapevine worldview might be put together to achieve what you’re describing. I use follows & mutes (and reports and zaps and maybe more) to curate a list of pubkeys-who-are-not-bots. I trust the not-bots list to use NIP-58 badges or NIP-32 labels to curate pubkeys who take on the “community authority” roles. I trust the not-bots list & the comm-auth lists to endorse credentials, but I give relatively more weight to anyone on the comm-auth list.