I truly don't understand that. Most people are sensibly averse to looking directly at the sun, but the warning is always given so long as I have been alive. One might suppose this could be relaxed once the eclipse is in progress and totality has been reached. I have been told that it is even dangerous to look at the sun at totality, but I can't credit it. The only thing you can see at that point is the corona, and the sky is brighter than that all the time, and we are in no danger from looking at the sky. "Look at it only through smoked glass." I have a hard enough time going out in broad daylight and being dazzled by the brightness.

Incidentally, there is a plot twist in the movie "The Four Feathers" (1939) where one of the characters (Ralph Richardson) goes blind in the desert from looking at the sun too much. (It is a great movie, worth watching.)