The problem with pushing custom REQ filters to the DVM marketplace is that relays will become obsolete.
Once this feature is mature, and nostr adoption grows, user customizable content feeds will be what sets nostr apart and keeps REAL user content visible.
Because the threat model from bots and bad actors will be always changing, end users will want to stay on top with the BEST content filters. They will benefit from sharing filters with each other, independent of the client used. If this functionality (to share prepackaged filters) is only available through DVMs, then nostr event traffic will gradually flow more amen more through these DVMs.
In addition, NIP90 for DVMs specifies an event to be published for EVERY request AND response. I kinda think this is overkill for the task at hand.
Just single event to publish the “filtering service offered” by a relay and another event to “subscribe” to that filter. This is the NIP needed. IMHO
nostr:note1aej3d6n9twm7y8vgvq8dq5aahhy0wkc900xpdh8n8a7rsxm0msdspyrf85
I never suggested pushing custom REQs to DVMs. I don't think DVMs should be relied upon for core features of the protocol.