How long will they last?
Some of us have wristwatches running, capable of being serviced, parts available, parts that can be fabricated, etc. That are 75 or even a hundred years old, with tons 50 or more years old, let alone 35 or so years still capable of and being used as daily wearers.
Even high quality quartz movements, like the 7548 and 7549 are more effort to keep running.
Watches 30 or less years old with dual display, digital, kinetic movements, etc. are even more of a hassle with unavailable parts, failing displays, failed back lights, etc.
I’m not even interested in spring drive.
I rarely get a quartz analog watch, have no plans done further dual displays, or digitals.
The quality of watches from Seiko and Citizen for a few hundred dollars, the lack of workmanship or desire to lovingly and longingly had finish every part in the movement, and overall sensation of a “soul” to a mechanical watch that can be used for generations vs a solar watch likely to be done for in a handful of decades does not really seem to create a market or desire for solar or quartz watches costing several thousands of dollars.