OK, then why is everyone saying it’s hard ?

The first reason, is because no one claims otherwise and, since Big Mailer Corps benefits from this situation, they’re not going to contradict it either. Big Mailer Corps BENEFIT from the myth that mail is hard as this means more people rely on them, they control more of the e-mail address space, and this translates to more e-mails being analyzed for targeted advertisement. The more people are discouraged, the more people will eventually subscribe to their services, and since they already control a large share, they can make mail slighly more difficult by making their requirements higher (harder, not hard). This is not something they do in some kind of conspiracy, this is just the result of them obtaining more power because people stay away from self hosting.

Another reason is because it used to be hard a long time ago. People got traumatized by how hard it was to not screw up and never reevaluated the situation. Some people today genuinely discourage other people from running their mail server, citing the very real difficulties they faced over a decade ago, far before some of today’s tools even existed.

And finally, another reason is that people keep repeating it without actually trying themselves. I know this for a fact because people have been telling me that mail is hard for the last ten years, and for the last ten years I asked what they found hard in order to try improving the situation. A VAST majority of these people confessed that they never actually tried: they read or heard that mail was hard, often from a source they trusted, then accepted that claim and started telling others that mail was hard. We can’t really blame them when that myth has been around for so long, if I had no previous knowledge of mail and did a quick search today to find out how to setup my server, I might just decide not to do it given how difficult it seems from reading others.