You're talking from the perspective of a pseudo-monopolist, which makes sense when we're talking about iPhones, but all it takes is one entrant charging lower p

You're talking from the perspective of a pseudo-monopolist, which makes sense when we're talking about iPhones, but all it takes is one entrant charging lower prices and your "best price in terms of total profit" calculation goes down the tubes as consumers switch over to the cheaper alternative. So you're right, a monopolist does not care at all what the costs of the inputs are but with competition the result is cheaper consumer goods (which has its own vices but that's a different issue...) Think about it; would you really want to live in a U.S. where every good was made in house? Your cashews would be very, very, very expensive.