Even in night light reading mode too much brightness from screen and also proximity issue
If the brightness out of the box is too high for a dark room even on the lowest level, I found the most effective solution was to install "Screen Dimmer" from the Play Store. This will display a tinted overlay on the screen which will act as dimming it down to very low levels. If you turn it down very low it does have a tendancy to slightly distort and drain colours, but that may not be a huge issue for you.
What is the proximity issue?
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