> because they cost more to build

Then they should offer models that are cheaper to manufacture, like the 5c. I'm surprised not to see a successor to the 5c. Maybe they are worried it would be too popular and gouge sales of flagship models negating some of their premium branding.

I'm currently on a 6s and see no update path for myself, I would happily sacrifice faceID and some of the higher-end phone materials for a modern paired down iPhone. I have about as much confidence in this appearing though as them fixing the state of the keyboards on the MBP's.