The tandem OLED screens they use on the iPad Pro stack multiple OLED layers on top of each other and reduces the brightness of the layers.

The brighter you run OLED, the more burn in you get.

The QD-OLED standard they tested in TFA is also supposed to be more burn in resistant, but they still saw burn in over time.

Menubar is going to be a killer

Screw us all with another fashion trend for terrible displays, just like when they switched to high-glare screens.

Not release it, as Apple only releases technology that has been perfected.