I think what he means is emissive in general. OLED, LCD, whatever, all are powering through ambient light, so need really high brightness in high lighting scenarios.

E-ink and these rLCD screens use the ambient light to their advantage, so they’re almost always lit at the appropriate level automatically, and you can supplement with much less fatiguing front-lighting in low light scenarios so you don’t have the emission from the display shining in your face.