Some of that is inflation (and it's claimed the iPhone 15 Pro at $999 is the best deal since the original adjusting for inflation). I also think that in order to continue shipping something new each year back in 2010 all you needed were some same-price-new-generation silicon/battery/screen improvements. These days the tech has plateaued a bit and we've seen a number of years where the improvements come from adding another camera, then another camera. More and more sensors. Some stupid and more expensive features like under-screen fingerprint readers. A phone could cost way less, but the table stakes are now much higher so manufacturers can get away with phones costing nearly a grand (and sometimes much more).