1. Email standards vs. real‑world enforcement
The core of the discussion is whether a missing Message‑ID header is a bug or a policy choice.
“Viva.com … sends verification emails without a Message‑ID header — a basic requirement of RFC 5322 since 2008.” – that_guy_iain
“Google Workspace rejects them outright.” – that_guy_iain
“It says SHOULD, not MUST, so how is it a requirement?” – st_goliath
2. Support teams as a barrier to resolution
Many commenters complain that the vendor’s support staff either ignore the issue or give vague, non‑technical answers.
“Their support team's response … ‘your account has a verified email, so there's no problem.’” – that_guy_iain
“The support representative just dismisses it, and it is doubtful an engineer even hears about it.” – ajross
3. Big‑tech power and its impact on smaller players
The conversation repeatedly highlights how Google’s (and other large providers’) rules can effectively block a small payment processor’s customers.
“If you want to send to Google Workspace, you MUST include a message‑id.” – thesuitonym
“Google is the one who's not RFC‑compliant.” – geocar
“The biggest war on small providers is waged by other small providers.” – Avamander
4. Pragmatic engineering vs. strict spec compliance
Participants debate whether to follow the RFC to the letter or to adopt a pragmatic approach that prioritises deliverability and business continuity.
“You should fix it, but the support representative just dismisses it.” – ajross
“The part about a payment processor not testing deliverability is wild.” – renato_shira
“You have to fix your email delivery settings (or find a better provider) for your domain.” – jeroenhd
These four themes capture the main strands of opinion in the thread.