Anecdote here, but any time I use dark mode even for a few minutes, it makes my eyes feel awful, and leaves ghostly shadows of text lines in my vision for up to a minute or two after leaving the screen. Reading anything in light mode on the other hand doesn't cause me much trouble even after hours of doing it nearly without interruption.. I have a hard time believing that i'm the only one. Personally, I detest dark mode and have never understood why so many people recommend it.