Earlier quoted context omitted.
iOS lets you turn on a red filter that disables the green and blue channels. you can set it to turn on by triple tapping the home button (or I'm guessing the back for new phones). This is the one thing I really miss after switching to Android. The red screen is fantastic for reading at night, really easy on the eyes.
My Android 10 Realme Pro2 has a option to desaturate screen every day at a fixed schedule.
This feature is not intended as a "night mode", it's very extreme. It also makes anything that has no red channel in its color disappear (although this is rare). I found it's a better night mode than actual night modes. But it's best if you're just reading text, for video or games it's probably too extreme.