I actually think your example illustrates this: people use their computers for porn. There's nothing wrong with that. If it's so large that he has no space left, I mean that's a pretty actionable thing to tell him. He's not an idiot for not figuring it out himself. That he "hid" the folder from you–I mean, people hide things from professionals all the time. Nobody volunteers to their doctor that they wipe in the wrong direction and thus have chronic UTIs. It's your job to work around the reasonable things people do that make your work harder and bring them to "oh, that makes sense, thanks" perspective.
You are just of bad faith, pretending to be outraged about what I said even though it only describes the reality of the world. Your newfound religion is so bad that you find offensive something that doesn't even have any moral implication to it and is factual proven by so many statistics that it is not even worth arguing about.
If you what you mean is "not every computer user is a moron" you need to work on reading comprehension because that's not what I said. I stand by my original statement and you are somewhat proving me right.
When asked about it, he doesn't have too many files. What do you do in that case? Isn't he a moron both for storing so much porn and at the same time (somehow) believing a tech support person wouldn't find the root of the problem. It was in a "hidden" folder, so not only he is a moron for the first offense, but doubly so for thinking a competent person wouldn't find something so obvious.
So, I reiterate, most people are morons, and technology just reveals their ineptitude in plain sight, it's simple as that.
You are free to believe in your idealized version of the world, but it doesn't match my experience at all.