As the documentation notes, inbound email is hard to set up properly if the service you're using doesn't offer good support for processing. I haven't set it up on my install and don't intend to for a while.
But with the new help button that appears on some pages, users are clicking through to the email commands documentation that they would never have found otherwise. It's not a huge deal, but this just cases confusion. It would be a bit nicer if it documentation for disabled features wasn't pushed in front of them.