I'm wondering whether any of you have seen any improvements on this front in the past year. Are there any new introspection tools to diagnose deliverability problems when they happen? New guidelines which verifiably reduce the probability of such problems occurring?
As an administrator of a small email server (with SPF/DKIM/DMARC/MTA-STS set up properly and a clean reputation of 5+ years), from my point of view nothing has changed, except perhaps for the worse. Email sent to Gmail users seems to end up in the Spam folder more often than before.
I wish people who praise Email as an example of decentralization working actually went through that exercise.
[0] yes it will show "via sendgrid.net" so perhaps by design the domain in "From" isn't checked, but still...
If you see it the other way around: why should they provide detailed infos for spammers on howto setup their own mailserver.
I always wonder why there is not a "Central" Service for each mail provider, like https://postmaster.google.com where you can register your domain and see what is wrong with your mails ... maybe even do "spam protection" by simply adding "mails per second" that you think are appropiate for your service.
Outlook is where my problems are.