Added complexity and technology adds to price and adds to things that can go wrong... But why are you here anyway, you obviously hate the idea of this cam?
I don't like this this particular implementation. Sony are masters of spoiling things:
1) Stupid auto iso implementation (too restrictive maximal ISO, no way to set up minimal shutter speed). Trivial implementation.
2) No DOF or at least focusing distance markings tool (must have for my purposes, so any optics without distance or DOF scale is excluded: no E-mount lenses for me, at least up to 50-60mm). Trivial implementation.
3) I still didn't get an idea how they managed to spoil 2nd wheel in NEX 5r/6. It is practically useless. Trivial implementation.
Personally, I'm waiting for further sensors advancements: photodiode closer to color filter that will help to relieve oblique rays problem (organic, BSI CMOS, etc) , electronic shutter, etc. A7's and A7r's performance with my leica asph optics is too bad. And it is not only underperformed with these lenses — I also dislike their look and feel.
BTW, I have a question for A7/7r owners:
With RX1 and RX100 I could set subject tracking mode, which is the superior substitute for focus-recompose: mark an object, recompose, magnify, focus. Is this function available with manual lenses? IMO it is greater than touchscreen for precise focusing: works for EVF, faster and doesn't ruin framing.