You're at the computer store. You're looking at laptops. On one end they have a row of Macs, all shiny and pretty. On the other end there's a few rows of Windows 7 machines, all in various states of usability. You also have a couple of Linux LiveCD's in your hand for testing.
You go over to the Windows machines and find one that looks somewhat Linux compatible and pop in an Ubuntu disc. It boot without a hitch.
And then you see, to your left, a grandmother, wandering about the computer area, confused as a duck in the Sahara. And you think to yourself, "Now, if I were a grandmother, what computer would I use?"
And you look at the Macs and suddenly they look easier, and faster, and better. You look at the iPad and it looks cooler and more capable of meeting your needs.
STOP. FREEZE FRAME.
Do you see what went wrong here? There are two main points:
-Your perspective of the grandmother is entirely based off of your stereotypes of elderly people. As such, trying to say, "this is what grandma would use" is next to useless, because by and large that perspective doesn't really exist. These people all have unique perspectives that you cannot assume in your mind without making some logical errors along the way.
Any time anyone ever says "Joe User" and uses it as an argument for or against a certain type of computer has not realized that the definition of Joe User is entirely subjective, and by and large, devoid of any meaning.
My mother could definitely learn to use Ubuntu. My grandmother could learn to use Ubuntu. Some of my customers at the retail store I work at, maybe not. The lady I spent about twenty minutes explaining the concept of an iPod to, maybe not. Simply put, generalizing all computer users as a mass that could never use Linux is a poorly misguided fallacy.
-This made-up perspective of grandma is entirely irrelevant to whether or not a computer is right for you, because YOU ARE NOT GRANDMA. Shopping for a computer is hard enough as it is; trying to do it with multiple personalities is even harder.
"But what if I was a (blank)," is a mistake because you're not. If I said to myself, "but what if I was a hardcore PC Gamer" then I would fail at my purchasing because I'm not a hardcore PC Gamer, and I don't have the same needs. I'd end up spending far more than I ever wanted to before, because in this fantasy where I'm consumed by my made up perspective, i'd need to buy a more powerful processor and an expensive graphics card, when in reality neither of those things are important to me.
If I were to shop as Grandma, I would be turning down a computer that works great with Ubuntu just because I think that my personal subjective perspective of Grandma couldn't handle the learning curve that I already went through several times and can now run circles around. I'm dumbing myself and my own skills down because people around me are not nearly as good at using Linux as I am.