At the time I got my MacBook 3rd gen in 2007, it was very good value (in terms of being well-engineered) for money. And it's still going strong, only had a memory and SSD upgrade since then. Particularly the battery is amazing, I still get 2-3 hours out of it.
I chose it over a ThinkPad at the time, which I considered roughly comparable, on account of the displayport. No other laptop in that price range had DVI out without an expensive dock.
The engineering sophistication is significant, but not in your face. Instead of cramming more electronics into the box, they work hard to reduce the parts count and increase battery life, among other things.
The engineering that went into the A4 is quite significant, but you wouldn't know it was there - except that the UI is very responsive, the unit runs cool, etc.
So you are right in a sense: people don't buy Apple products for the engineering - it's the design. But the engineering makes them not crappy. So they keep Apple products because of the engineering.
And if people were flocking to Apple computers on the strength of their engineering, I'd agree with your point.
However, Apples' recent success has been because of its design sophistication which Jobs is rightly seen as the inspiration for.