People who complain about self hosted email, are always complaining about interoperability with gmail.
They base their entire argument about self hosted email “sucking” and, and “being hard”, by how it interacts with google.
Alternative paradigm:
Google is evil, stop supporting them. Focus on people who are up to speed. Let normies normie, and fall off. You advance.
I self-host email and only had problem once with gmail regarding ipv6, then I set my server ipv4 only and it works with the devil. I know, I should block them all from gugol.
Self hosted email is easy. Google requires you to register DNS cookies for your email domain if your IP4 is not a class C or better (or you are IPv6). That is evil, yes.
Dealing with spam is NOT so easy. One low tech way is to give out a unique email address to each correspondent (just edit the aliases file, or use a simple gui that automates most of this).
I wrote the pymilter package to make custom mail filters for sendmail and postfix coded in Python. I use a bayesian filter.
At this point, 90% of spam comes from gmail.com. I am about to make that domain "whitelist only". But in case it is a legit would be correspondent, what method could I offer in the rejection message (not that anyone ever reads the rejection message) for requesting contact? Maybe tell them to use XMPP or IRC? That is beyond most "normies" as well.
Great now I have something else to learn about
