Bulky? Costly? Software doesn’t support it? How much do they cost, anyway?
I bet they’re also absolutely awful to read/write text or code on. And the quality for 3D uses is still mediocre.
I could imagine their having an application in CAD and 3D modeling if the price were right. But the software tooling would first need to be able to support the display. And I doubt that’s a dimension (ha!) that would be worth their while to compete on (bit of a chicken/egg problem).