Comment by shkkmo

It's weird so see such a factually incorrect comment so high up on HN.

SPF/DKIM is literally how you establish sender identity instead of relying on the IP address of the email server so it is ironic to claim that they have anything to do with server reputation while lamenting a lack of sender reputation mechanisms.

Currently, SPF/DKIM are mostly used to prevent fraud, but they also provide the best tool we have to build sender based reputation systems.