Fabrication of any kind of semiconductor is full of fixed costs. Not only are the yield rates low, but your cost per panel increases dramatically since you have

Fabrication of any kind of semiconductor is full of fixed costs. Not only are the yield rates low, but your cost per panel increases dramatically since you have fewer units to spread over all your tooling and fab buildout. It's also risky as hell - making a high-DPI LCD panel isn't like making a rocking chair in your garage, there is an enormous startup cost. It takes a large measure of guaranteed demand for anyone to drop that kind of cash. The only people who have been able to move the needle on this sort of tech and fab are Apple, Google, Samsung, et al. They're the only ones who can go up to a OEM and say "I want you to build this brand new part, to these specs, and I can guarantee you millions of units". Short of that the risk is insanity, and the OEMs themselves are unable to create a market for these new parts themselves. If they came up with an innovative, new LCD panel, they'd still have to wait for someone else to throw it in a shipping product before real demand materializes. I think there's a rational reason why the big, vertically integrated companies are the ones driving new panels.