Just like there have been amongst goyim very many marital crises, separations, divorces, murders even, caused by husbands finding their wives (and vice versa) having "a chat" on Facebook with a previous lover or boyfriend from 10, 20, 30, 40 even 50 years ago, so similarly one reads of whole Haredi families thrown in to turmoil, ruined even, even becoming instantly unobservant of mitzvos, by a father, mother, son or daughter found watching porn on the internet.
To most of us already sullied types, that may seem like a joke.
But if you're a person who has not seen it before in your life ever, to suddenly see it in actually reality for the first time ever, can be a life changing experience, especially for protected Frum girls, akin to the moment when the Serpent in the Garden of Eden had sexual relations with Eve, as the Midrash says, and thereby ruined mankind!
The Chazon Ish and the rabbis in 1950 were literally prepared to martyr themselves & their daughters to death to prevent Ben Gurion's plan of forceably conscripting all Haredi girls in to Zahal, because they knew that there they would be be immediately deflorated, unfrum, and turned in to Jewish harlots, with the result that the 1 million+ strong Haredi world would literally not exist today!
The Internet is now viewed by the Haredi as much more of a threat to their existence than even Ben Gurion! Kehillos make their members sign that they have no internet in the home, and those that are found with it, their children are expelled from the Haredi schools.