I was just about to create this same thread. It appears that the Autodiscover gets painfully close to working but just not quite there. I was hoping that v14 had better results than v13, but no such luck.
I've recorded a quick 3-minute video that showcases our setup for the DNS, how the Outlook Connectivity Tester tool shows no issues, and how Outlook fails to set things up properly:
That video shows Fiddler monitoring the network traffic and it appears that Outlook is trying to connect to the wrong host / url despite the SRV record telling it otherwise (and even prompting me to allow a different domain).
What I think is failing in our case is the inability of Outlook to set the "Outbound Requires SMTP Authentication" flag - as the video shows, when going into manually configure settings everything else is set correctly.
Incidentally - I had thought that maybe autodiscover was only available if Exchange ActiveSync was enabled (even though SmarterTools does not clarify that as a requirement or not) so I did pay to enable it on some mailboxes and tried those with the same results - close, but no cigar.