I agree with your point (assuming you are talking about a decade ago, I expect the computer access issue has changed slightly) but that doesn't counter the GP's point of the tech industry isn't the one doing that discouraging.
In the 90s (when I was a teenager) girls looked down on geeks (then again so did most of society), allot of the time computer science had the same set of questions to answer as theoretical math "What good is it? What can I do with it?" In the 90s tech was only making large effects in very limited areas. Compare that even to Civil, Electrical and Mechanical engineering; you can see the bridges, televisions and cars respectively. Only recently (say the past 5-10 years) did the effects become easily visible to the general population.