They're going further: this would likely be incompatible with email services from other providers such as fastmail.

I do that all the time without any problems. What issues have you seen with it?

marked as SPAM. I get that a lot

DKIM sign emails and fix reverse resolving. Had that problem too, I was highly pissed off that DKIM signed emails were still regarded as spam, even if there is no way to forge them until I fixed reverse resolve.

Anyway, I dont know anyone relevant to me who is using gmail. Most of them are tehnical and they all stopped using gmail years ago, also more and more people are moving to self hosted solutions.

Not good at all. This should happen only if one of your servers has been compromised and spits out spam that gets logged by Google. Does unmarking your email as spam by the recipient work? If not that would be an indication it's intentional.

Most of the big providers are shit, I wish I could shame them, but alas, I can not.

If I'm responding to e-mail from their users, I expect at least my initial response will get through. You really don't need any fancy crap like DKIM/SPF/nice IP addresses database/AI/bayes/etc. in this case to make the decision if e-mail is legitimate.

All my responses contain randomly generated ID of the message I'm responding to that nobody else than the sender and the intended recipient (me) can know. If it matches one of the e-mails their user sent me, say within a reasonable timeframe, and it's a first response or so, it is almost certainly genuine.

It just shows how little they give a crap about their own users, if they don't make such a simple check to make sure that their users can get responses to all sent emails.

Instead of making e-mail work, they're inventing bullshit like this new "expiring email" thing and making redesigns nobody asks for.

Interesting. I can't say that I ever get that, and I email Gmail a ton. I'm curious if Google outlines how to prevent getting considered SPAM or not. It could be that I've had my domain for >5 years as well.

Absolutely no problem if you set up your server correctly.

Half truth, the age of the domain matters.

But how can they now that? I've got a German domain and denic doesn't list the registration date - only the last update...

An email server discriminating about what messages to accept is not breaking anything about the protocol or standards.