Do not underestimate Apple’s R&D costs. While yes, the new iPhones barely look different, their internals sometimes change drastically and especially the new processors are quite a feat every year. Apple‘s ARM SoCs have consistently been either among the top performers in the industry or, especially lately, the top chips outright. There’s massive R&D behind that. If course, they still have a hefty profit margin on every iPhone but it’s not just slapping a USB-C port into last year’s devices.