I’m a fan of dark themes over black themes, and while the new dark theme isn’t exactly a black theme, it’s still very dark. This means there is a lot of contrast between the white text and the very dark background.
I currently use darkreader to theme the website and it allows me to adjust the contrast and the brightness of the theme. It would be nice if there were some similar settings with the dark theme on GitHub or at very minimum the option to select between dark and very-dark themes.
Personally (and this is obviously a matter of taste), this level of “darkness” and contrast is what I think to be close to optimal: