> manufacturing limitations mean you can't easily have those per-pixel while still keeping the whole thing cheap
“can’t easily” seems to imply it is possible. If that’s true, Apple, with its deep pockets, should be able to do it.
Also, I don’t think Apple will be bothered much with “keeping the whole thing cheap”. They will want to prevent it from getting expensive, but likely will accept intermediate costs if the result is much better.
If you have a display 1000 pixels tall, then the brightest LED's are on for 1/1000th of the time.