The established ideal for comfortable and efficient reading is a line length of 45 to 75 characters. Most studies show performance peaks within this range. Under WCAG it's a legal requirement for website line lengths to be under 80CPL because of this.
This rule is applied in the majority of good professional print. Well-designed novels and the columns in magazines are formatted to stay within this range, as a single line across a wide page is fatiguing for the eye to track.
https://practicaltypography.com/line-length.html
https://stu.westga.edu/~ssynan1/literacy/Dyson.pdf