I’m the type who usually gets a new iPhone every five years or so but I rarely ever get the latest version, as my provider used to offer me free ones but they were usually one generation behind. But last year when I was having trouble with my iPhone XR I ended up getting the 16 because the price difference wasn’t that much higher than the 15. And since I was buying it outright I figured I could get longer time with the 16 before they stopped the updates.
So hopefully I won’t have to replace my 16 until the 21 or 22 comes out