That sheet of paper is an excellent example, actually. You'll see the sheet of paper in direct sunlight, and it'll be as white as white can be. But if you then take it inside and hold it next to a lightbulb that emits a warmer, yellower light, the paper will appear less bright, and more yellow. But it's still white. And if you then turn off the lights and light a candle instead, in the soft orange glow that white sheet will be even darker, and more orange-y. But it's still white.
Apple's 9-inch iPad Pro specifically adjusts the display color balance so that white on the screen should always appear like a sheet of white paper in the same lighting conditions. So in that candle-lit dark room, a white screen with black text will look just as dark and orange-y as a white sheet with black text would. It's not colour-accurate in that it shows you the white background as the sunlit white you'd see outside, but it is colour-accurate in that it shows you white as white would naturally appear in those circumstances.
In the end, this is perceived as more natural, and it doesn't feel like the screen is orange. The screen appears to be white, as it looks like a white object would in that situation.
This differs from settings such as night mode or f.lux, which don't adjust based on the ambient light but just remove an amount of blue. That still makes it easier on the eyes, but it doesn't look as natural. And will look pink, or orange, depending on how exactly it differs from the ambient light.
Generally, many people find a feature such as night mode to be easier on the eyes when working in the dark, and if it's done correctly (Apple did great with the iPad Pro) it does not make anything seem out of place or unnatural.
It is not a feature that lends itself for colour-critical work such as photo editing or print work -- here you'll always want the screen to show how an image might appear on that bright, white, sunlit page. It's why this kind of feature usually has an easily accessable off-switch.
In short: Some people like this kind of feature, some don't. So as long as it's an option and not forced, everyone can choose to use it. Or not. And everyone is happy.