Research (see reference below) demonstrates that 100 characters per line is the optimal length for on-screen reading speed; but it’s not what people prefer. People read faster with longer line lengths (100 characters per line), but they prefer a short or medium line length (45 to 72 characters per line). In the example above from the New York Times Reader, the line length averages 39 characters per line.

https://www.blog.theteamw.com/2009/10/26/100-things-you-should-know-about-people-2-line-length/