The problem with this line of thought is that you're talking about the older generation (our mothers and grandmothers).
Teenagers today are power users, except for those who have much bigger problems than poor technical skills (like being freaking illiterate).
So shouldn't we optimize for our children instead? Isn't it plain stupid that we spend so much worrying about our mothers and grandmas?
The side effect is that we, as a society, are making efforts in keeping people dumb. Reading, as a skill, is hard to learn and it was considered optional and for power users even in the 17th century. Even today, I find it so stupid that movies are dubbed around the world, as if people can't be bothered to read freaking subtitles. That's how I learned English btw, something which would have never happened if I lived in Spain or Italy.
Do you really think teens today are power users? Every generation since I was a kid thought their kids were tech geniuses; having interacted with them, I know it wasn't true. So kids today use Facebook and Instagram and Snapchat. And Tumblr. I haven't seen any kind of trend for teens using Terminal or rolling their own. They appear to be proficient because the tools for normal people have gotten so much better.
Yes, I really think teens today are power users. I also interact with plenty of teens and also my wife works at a kindergarten - she has 4-year olds that know their way around a PC, enough to open their game or a browser.
Being a power user doesn't necessarily mean usage of a terminal, especially since most teens today use Windows on their PC, which has the shittiest terminal experience of them all. Heck, when I was a Windows user I wasn't using the terminal either, even though I was doing programming. Even if you are using the terminal in Windows, you don't really have much need for it since the whole freaking OS is anti-terminal and you can't do much with it. It's easy to forget this if you're a Mac or a Linux user.
This is not about teens being smarter btw. Older people simply don't have the patience to learn anymore, unless they see the real value in doing it. My folks also have a huge language barrier - they never learned English, as they were taught Russian and French in school and they forgot everything due to a lack of practice. For my mother, it doesn't matter how easy to use the device is, if it isn't localized.
Our tools definitely got better, but the only truly meaningful thing that changed since the late 90 is the availability of the Internet. When I was in high-school, in year 2000, we had no Facebook or Twitter, but I still had classmates that were communicating a lot over IRC and email. But they were doing so from school, because home Internet connections were expensive and shitty.