I also have mild astigmatism, but I find I prefer dark themes nonetheless - I think it is legitimately a little harder to read, because I just tabbed over to Di

I also have mild astigmatism, but I find I prefer dark themes nonetheless - I think it is legitimately a little harder to read, because I just tabbed over to Discord to check and realized I was using a larger font size than I'd usually use in other applications, and that the text definitely was a little harder to focus on compared to white-on-black text of the same font size. It's just that I like having my backlight blasted in my face even less, so it adds up to a sufficiently more pleasant reading experience that I switch everything to dark theme when I can.