Google long ago dropped “Don’t be evil” from its code of conduct, which I take to mean it no longer pretends to avoid it. We have watched Google enshittify its search engine, and now it is working on Gmail.
The way things were
It was (and for the moment still is) possible to set up a Gmail account to
fetch mail periodically from a remote POP server and to “send as” a particular
identity through a remote SMTP server. You could run a mail server for
your.example.com, read what it received from your Gmail account, and reply
from Gmail with the message originating from your domain’s server, so
SPF,
DKIM, and
DMARC all worked correctly.
It was not perfect. “Periodically” meant the delay between a message arriving at your server and appearing in Gmail could be arbitrarily long, often 5 to 15 minutes. The alternative, having your domain server forward mail to Gmail, typically breaks SPF, DKIM, and DMARC, and it risks Gmail classifying your server as a spam source, because you are forwarding (to yourself) the spam your domain receives.
They made it worse
Google announced it was removing the POP fetching service. You can still forward mail to your Gmail account, but that has all the problems described above. That led me to write gmailSender, which uses the Gmail API to insert mail directly into your account from a domain server. It is described in Forwarding to Gmail via API. It can be fairly involved to set up. I have tried to make the README clear, but it still takes some technical knowledge to get gmailSender working for a given domain.
They really made it worse
It has become apparent that Gmail intends, as of 2027 to remove not only POP fetching but also the send-as ability. You will no longer be able to use Gmail to reply to mail received at another domain as that domain. Your mail will come from Gmail, and unless you use a gmail.com address or host all your domain’s mail on Google, you will break SPF, DKIM, and DMARC alignment.
Why do this?
We can only speculate. The stated reason is that maintaining these services is too costly, but it is telling that Google is not providing them even to paid accounts. So Google believes people will keep paying even as services they have relied on for years disappear, which is more or less the definition of enshittification. Lock-in is probably also a factor. If your domain and all your mail services must be hosted at Google, it is harder to switch providers, and all your email is available on Google’s servers for its AI training and advertising businesses. If you are not paying, you are the product. With Google, even if you are paying, you may still be the product.