Yes. Mute and follow only go so far. An explicit “is trusted” marker will be needed to implement Web of Trust over Nostr. Making “is trusted” markers private will help keep influencers and money out, but these and bots will always be the challenge of better WoT tools. 

The pioneering of WoT for social media is Nostr’s game to loose. Along with “crowd recommendation” of content and follows (and “other stuff” users want) “trusted” advertisers and products will also thrive on the Nostr network. 
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