A working standard is certainly an issue. The other main problem in this area is that the although people have the technology to receive these wonderful displays, broadcasters are not ready to upgrade to deliver on these wonderful displays. Many broadcasters just upgraded to 1080p and are not quite willing to go to 4k yet, not until their costs for 1080p have been paid for.
Broadcasters were looking like they were ready to make the jump to 3D, then 3D TV sales tanked.