Input Make greylisting a last check in mail processing queue?

[websavers]

This discussion on reddit about greylisting from 4 years ago has a good rundown as to why this is a more useful implementation for greylisting:

https://www.reddit.com/r/sysadmin/comments/yc3wqx/is_greylisting_still_viable_in_spam_protection

The gist is that:

1. Today, users expect email to be near-instant, while greylisting can delay messages
2. Servers that send using round-robin get rejected entirely because they aren't sending from a consistent IP that allows for the necessary number of retries. This means the Plesk server admin must keep on top of manually adjusting their whitelist with mailers that use round-robin sending

Given the high potential for either delayed or dropped messages that are important like 2fa messages, the suggestion in that reddit thread to make greylisting apply only after receiving an SPF none and also perhaps after a certain Spamassassin threshold could be a viable solution to keeping greylisting useful.

Otherwise users are keen to simply disable it, which isn't an advantage to the overall health of the mail server.

Thoughts?