This makes the same false assumption about the world when applied to computers: The world does not exist of a binary-human type: people who are experts and people who are not.
I own a 28-year old Volkswagen van. It is completely hackable: the only electronics are three relais. But I don't hack it all by myself. I still, gladly drop it at the local garage to get something fixed. I can stop in nearly any town at the local garage and get stuff replaced, fixed or solved. I've had a waterpump fixed in Germany, my brakes replaced in Sweden, the battery replaced in France and so on.
And that is where the importance of hackability comes into play. Not the fact that /I/, myself can open up a browser or tweak it, but the fact that someone in my proximity can. Instead of having to ship my Macbook-pro to the US to get a fan replaced, my local fixit-guy can open my Thinkpad and replace the fan. Instead of having your computerized and closed-down car towed to the nearest official BMW-garage, I can drop my car at any place where they have a set of screwdrivers and some nuts and bolts and have it fixed.