It wouldn't have, apparently. An optometrist friend says that sort of thing only makes slightly worse the things that were already going to happen to your eyes. Like, if you are nearsighted and didn't exercise your eyes looking at far away stuff enough, your eyesight will be slightly more myopic. But you were going to be nearsighted anyway. Like, people were awfully nearsighted way before the invention of the television and sedentary indoor lifestyles. We just hadn't invented optometry yet to note it.