Between wearable devices and car infortainment, the latter has better chance to boost display market growth. Wearables will have smaller display and will be full of high end mems sensors and IC devices. However the car infortainment will need high end display devices and touchscreens for entainment purpose. Also the flexible displays can find better market in automobiles than anywhere else.
I donot think that technology has reached a dead end but its premature market. Mostly there is little content available for 3D TV. Unless there are thousand of movies, series, commericals and general content available i do not see 3D going anywhere. Also, the consumer hardware that can capture 3D videos and pics should be first thing to develop to increase the 3D content.