alt Hacker NewsFor people with astigmatism, black in white is generally easier to read than the other way around: https://graphicdesign.stackexchange.com/questions/15142/whic...
Of your criteria is battery life, dark mode is most likely better
If your criteria is eye damage/strain, then IIRC the research is divided on this topic
dark mode is easier on battery for OLEDs but not on LCDs where black needs the pixel to be fully active (white is off, black is on).
black on white is easier to read than white on black full stop, no astigmatism necessary.
https://esa.org/communication-engagement/2018/08/03/resource...
ambient lightning is highly recommended to not strain your vision.