Well explained, I hadn't really thought about filters as a vector of trust before.

It's interesting that you didn't call out web of trust as a spam prevention strategy, because that is implicitly the subject of the post.

Web of trust seems to work pretty well on nostr for reducing spam, but ironically destroys something like bitcoin which requires global (objective rather than subjective) consensus.

I happened to be reading about XRP this week (don't ask), and discovered that in lieu of proof of work, or even stake, their sequencers are validated by being included on other nodes' "UNL" s, or "Unique Node Lists", and don't receive fees for mining blocks.

These lists have to be meticulously curated, because any significant deviation between node policies will delay or even stop the network. At best, this curation happens on the social layer, and is in no way adversarial. If you break social consensus, you get kicked off the island and lose the ability to sequence transactions. XRP has 190 nodes, but only 35 are generally trusted to validate the network. To make matters worse, XRP curates a UNL which they encourage the network to use, and "carefully vet" node runners before including them. XRP is completely permissioned; it is no more decentralized than the Fed's board of directors.

I write all this because XRP demonstrates that web of trust is inherently exclusionary, and can only work to the extent that that is desirable (as in a "compliant" digital currency). It may have a minor role to play in decentralized systems, but only to the extent that those systems need not be considered "open", i.e., permissionless.

Again, this is ok for curating feeds on nostr, because I do not want access to my attention to be "open". Network partitioning is part of nostr - there is no "global". There is only my subjective, incomplete view of the network. Strategies other than web of trust are important for bootstrapping new users' reputation. But money has to work for everyone, at all times, and requiring reputation to transact essentially creates a social credit based permissioned monetary system.