Earlier quoted context omitted.
I don't think that's true. If my BOM costs go down by 10%, I don't need to charge any less money for my product. If Apple could build an iPhone for 1 cent, why wouldn't they still charge $1000 for it? They can say it's how much iOS costs or whatever. (And hey, use the extra profit to hire more tax-paying iOS developers, making iOS even more valuable.)
In economics the closer you get your price to be MR=MC the better off your profit. If they did as you said more than likely they would be leaving money on the table. This is usually a fairly common intro economics problem as it can seem unintuitive to lower the price to make more profit. Now iPhones do have somewhat of a 'monopoly' effect. But only to a point. In a monopoly you want MC=MD. https://openstax.org/books/…
It's Apples install base, app ecosystem, and social moat (iMessage) allows continued high gross margins on their hardware and locks competition away from their profit center. The sale price has very little to do with the marginal cost of production and a ton to do with a naturally occuring software monopoly.