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MTA-STS is useful (but it's about helping receivers by demanding mail is sent encrypted, not senders with delivery).

BIMI is a pay-to-spam protocol that helps senders, you can add a rule to postfix to mark it as such.

APRF is a draft, and likewise helps senders, not receivers.. not sure why anyone would want to adopt this standard. A little closer to DMARC reports, but sharing PI that you owe no sending server.

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