You have to understand that telling the spammers each and every detail is simply not viable. So you're gonna end up with situations where lazy/uninformed postmasters get caught in-between, sucks but unavoidable.
You have to understand a rejection is not telling every detail. And diligent postmasters have observed Google and Microsoft drop email from low volume senders with faultless configuration and reputation.
> Sometimes it's too much info to give out. You want to accept phish/malware and silently drop it so that the bad actors don't know you've detected it.
Users' interests are served by being informed when this happens. And plain text correspondence is not easily mistaken for malware.
> A perfect technical configuration doesn't make you inherently trustworthy or provide you with faultless reputation.
