Dell announced a 30" OLED display in 2016; then it re-announced it (for lack of a better term) in April 2017: https://www.anandtech.com/show/11272/dells-ultrasharp-30inch... and since then it seems that nothing public has been said. I wonder what happened in there: two years of vaporware is unfortunate, although I have zero technical expertise in this domain, so there are likely good reasons behind the scenes, even if I don't know what they are.

OLED TVs are common, but something keeps them from being commonly used as computer displays.

It's the burn-in that keeps them from being acceptable computer displays. Computers are more likely to have static parts of the display that initiate uneven burn-in.

Yes, and what is that exactly? I need OLED displays.

I thought the "burn in" on OLED screens can be reset?

It’s actual degradation of the light emitters which age with a function of on time. The only way to fix it is to drop the intensity globally to the level of the weakest emitter, assuming they all degrade at a known rate.

Burn in is not an issue in any practical sense now. Sure you can buy a phone that uses lower quality components and experience severe burn in, but then why are you judging the displayed technology by sampling a low quality device?

The situation in the phone market is much better than full size monitor market. Without the market size and scale to support, its hard for LED monitor to improve the yield and sell in more competitive price.