The difference I see here is I don't think there's some sort of prevailing idea that young people all know how to fix their cars, like there is that they know how to use a computer.
Not that they did, mind you. It was enough to know a few makes and models so you could say "Gee look at that bad ass Thunderbird with a hemi!" when something cool drove by. That, and everyone had to pick a side in the Ford/Chevy debate, with a few parroted opinions to back up your choice. Actual mechanical ability was something most people just pretended to have.
To be honest, it's not that different than with computers these days.
Knowing the technical difference between China's great firewall, the NSA's snooping, and the the UK's proposed porn filter is vital for people making decisions about them, as well as educated voters.