Marc, I think much of what you say is very true but more in tune with how the world was and the reason why many professionals and amateurs (myself included) chose the path of a large financial commitment in MFD.
The lines now are vey blurred in the image capture of today and while there are still people who want BIG prints, (Gerald springs to mind who sadly was chased away) much of the work, especially in the professional market never see anything over A4 and is increasingly web based.
I enjoy using my Arca and Phase back in very much the same way you use your S2 for fun and apart from the Architectural stuff I shoot (where the Arca comes onto its own) everything else is shot on a smaller format (professionally)..... just no need for bigger reproduction and the quality is staggering if lighting is right.
If then MFD is ever becoming a enthusiasts, luxury format, maybe Hasselblad can nip the bud early in the smaller formats as we all start converting to our iPhones as cameras of choice?
I won't ever buy a Lunar but I do get the idea behind the concept.