For me, the primary value of my phone is the camera, and the telephoto on the iPhone Pro Max models has gotten significantly better in the 2.5 years since mine was released.
Were it not for the camera, I could have stopped upgrading 10 years ago.
My point is, not everyone values the same things you do. The new Siri AI only runs on 15 Pro and higher, I think. New features do arrive in newer phones.