I don't play games on my phone, so it really does everything that I do often that I want it to. When I look at what else I own that it could replace, I can't see other easy wins.
Modem and CPU efficiency improvement from Shrinking Node.
Thinner iPhone, Sub 6mm from its current 7.8mm.
Battery Capacity improvement, Super Fast Charging, Battery Cycle ( Which Apple has kept it just above 2 years under normal usage ).
All while staying within the current 170g weight if not lower.
That is a lot of iteration, and enough work for at least 5 version of iPhone.
For a lot of people, Phones has reach a good enough point and buying another one is simple because of MNO contract expiring or Battery degrading they are buying a new one.