First off it was a 16 year old. I have more experience using the internet than they have experience living. Extend that out to 25 year olds and I have more experience dealing with desktop computers in general than they have living.
No, people under 20 do not have the most experience online. That 7 year old doesn't understand anything about what they're using, it has been made so that they don't have to. People mistake no fear of using something as experience and knowledge of that thing.
That 7 year old doesn't understand shit, they're just not scared of braking it and having to pay for a replacement. The majority of teens fall in to this as well.
We don't mistake the almost ubiquitous use of cars in the US as an indicator that the US population is 'car savvy,' so why do we do it with computers, cell phones and the internet when in reality you need to know just as much about how they work as how your car does in order to use it?
Simple use is not understanding.
And Tay is a better example of the failure of American society to raise people than anything else. Microsoft didn't have these problems in Japan or China.
And honestly, you want to talk about outliers and than use 4chan users as some example of 'the current generation?' Hell 4chan users themselves are not some coherent group.