I think I'm having flashbacks :P https://news.ycombinator.com/item?id=9224
I absolutely agree that there’s a need for the middle ground.
I’d also say that I think nobody really cares if GH is running vanilla git, or which SMTP and IMAP server Fastmail is using; perhaps the important thing is that there exists at least one maintained fully API compatible open alternative, not necessarily 100% identical to the software run by the hosted, or even primarily developed or maintained by them.
(And, well, the insight that can be derived from metadata is not to be dismissed, so I wouldn’t agree on “almost irrelevant”)