As a specially trained valuable first world labourer -- at least, my employer seems to think I'm worth a salary -- I find growing my own potatoes (and a few other things) a welcome break from my desk and screen.
I'm sure my garden is nowhere near as efficient as a real farmer could make it, but that's hardly the point. And a few rows of potatoes (even with my inefficient management), are a much more productive use of the land than a typical suburban lawn.
In my comment, GP is pjc50; not you. You literally said that everyone should plant potatoes, which I, and pjc50, disagree with. As I said before, do it if you enjoy it; it's not a great use of everyone's time.
Wait until you find our how little of the world's population builds and maintains the telecommunications, liquid fuel, and pharmaceutical ecosystems that we also reply on.
Growing part of your own food is a good idea. We should all plant some potatoes this year – a not so laborious way of producing nutritious food.