My point is that Apple is not subsidizing lower end models by selling overpriced ram, if they were fine with the margins other laptop manufacturers have, they could sell their products much cheaper (they could still cut their prices significantly and have considerably higher margins than others) but they don't, because they don't have to (their products are good, there is a huge demand for them and they don't have as much competition as PC makers).

Obviously I don't Apple's exact margins, they are probably lower than 50% but not by much however: "But there's no way they could keep their entry level prices as low if they charged a fair price for upgrades." is simply just not true, they obviously could do that if any of the conditions I mentioned changed, they just don't because as any other company Apple seeks to maximize it's profits.

Dell XPS, Thinkpad X1, Razer Blade and Surface Laptop lines have pretty decent build quality, of course they all have inferior CPUs which use more power and generate way more heat compared to the Mac (I didn't say you can get one for 1300€, just that that other manufacturers try to price their premium laptop lines at similar level as Apple but usually end up having to sell them at significant discounts)