The long and short of it is that some people want Apple to make barely any or no margin. They see companies like Xiaomi with 5% margin and expect Apple to also make a 5% margin.
I have never understood this logic that an Apple product is overpriced just because it's selling for more than the combined cost of its components.
Even when you eat outside at a restaurant, the final price of a dish is definitely going to cost way more than the price of its ingredients. There are other costs to factor in - from the rental, to labour, and of course the shop has to be able to earn a decent profit at the end of it all to make their efforts justified. You are basically paying for the convenience, ambience and experience.
When I see a doctor, the money I pay for is many times more than the cost of the medicine dispensed. I am essentially paying for the doctor's expertise in knowing which medicine to prescribe.
Same logic here, IMO. Yes, an Apple product may sport many off-the-shelf parts, but who amongst us is able to just buy them off the shelf just like that and assemble them into the desired end product? That to me is what I am paying for when I buy an Apple product - Apple's expertise in being able to put all these parts into a product that affords me that unique user experience (made possible by Apple's control over their hardware and software) that no other company that provide.
That, amongst other things, include the underlying OS and the services accorded by the ecosystem (iMessage, Siri, Apple Pay, maps, amongst others). These are provided free, but cost money to maintain, and their costs have clearly been worked into the final price of the product).
I see it as a virtuous feedback loop. Apple's profitability is proof that they are still making great products (flaws and all) that people are willing to pay a premium for, because the critics ultimately forget that Apple sells a user experience, not raw paper specs. It is this profitability which in turn enables Apple to keep improving their products to the point where the competition simply can't keep up (for instance, there is no tablet market, just an iPad market).
I always find it hilarious when the critics call for consumers to vote with their wallets, and then act all shocked and aghast when the people proceed to do precisely that. Just not in the way they wanted.