I've been in IT since the 1970s. The decrease in women in the field is striking. The article you cite is correct to make the connection to CS degree representation. Prior to the 1980s, CS degree programs were nascent if they existed at all. Not requiring this qualifitcation allowed an amazing diversity of people to enter the field.

Steve Jobs was in a way quite typical of the sort of people who showed up in the IT field. He would have a tough time getting hired today.