There are a host of things to remember:
1. Solar power is great until you remember that it's not always sunny; flexible PV arrays are on the order of 10-15% efficient (ballpark); and it would take a fair bit of PV area to work well.
2. 1000 shifts in a 2005 Campy publication. That is given Campy's ideas/theories/working models then, as well as technology then. Battery technology is improving, and I'm sure that Campy's system efficiency is improving too.
3. Bluetooth or other wireless connectivity to derailleurs is unlikely given the effects of interference and low power on that connectivity.
4. Mavic's last electric system--Metronic--wasn't that bad, at least to some. I know a few people that are still using it.
5. Electronic systems could offer the benefit of automatic trim.
6. An electronic system will have to have a "get home" mode for when Murphy throw his law in your face.
7. There's always going to be development on something "better." That's the nature of manufacturing.
8. There's was a lot of worry as indexing was released and as integrated shifters were released. There's always resistance to change. If there weren't, how else would you explain Grant Peterson?
As for supply searching for demand....well, that's not really an argument. Everyone on a bicycle today is taking advantage of some development that wasn't absolutely essential to riding a bike. There was no demand for velcro before its inventor got the idea for it. There's nothing in economics that says that supply can't generate demand, and there's naught wrong with that happening. If we only got what we needed or what there was a demand(prior to its invention) for in cycling, there wouldn't be much of a cycling industry.
Personally, I've no interest in such a system. The efficiency of current systems is about as high as such things can get, and I like the mechanical feel. I also enjoy he lack of dependence on high tech. Sure, the battery in my power meter can take a [censored], but I can still ride without my power meter. I'm also just one customer, too, and I'm sure that there are quite a few folks who would want such a system. And who knows, it could turn out that such a system was great, earth-shattering, or whatever, and my mind could end up changing.