[sneak]

"ideally shouldn't happen" doesn't mean the deliverability cartel doesn't block you anyway.

Gmail et al have been spam filtering messages from correctly configured mail servers for a decade+ now. All the dkim, dmarc, and spf in the world won't help you if you aren't known to them.

[systems_glitch]

Pretty sure it's part of the plan. If you're hosting your own mail in 2023, you are the resistance.

[MengerSponge]

More like plenty of spam comes from correctly configured servers.

[systems_glitch]

Sure, that's almost certainly true, but the arbitrariness of changes and blacklisting leads one to consider perhaps they don't care at all about small hosting operations.