You =! Everyone
You believe computers are commodity items because you're a regular buyer of cheap laptops, and cheap laptops are indeed a commodity item - all built down to the same low expectations, defined by price, branded up under an infinity of names but all essentially the same product. If they work for you, and (perhaps more to the point) if you're prepared to work for them by reinstalling every couple of years and working around all the niggles, that's great, you're saving money, good for you.
But that's not for everyone.
In the same way that not everybody wants to drive a Chevrolet Matiz and not everyone wants to drink Tesco Value Lager, not everyone wants to buy a £400 laptop, or even a Windows laptop of any price. Some people *choose* to pay more for a better product. That's the concept you're going to have to get your head around, because those people aren't about to change.