There's incremental and there's not very noticeable though. Coming from the 14 or older is massive. Coming from the 15 is less so
Why is that a bad thing? These are not just mature devices now, they're also expensive. I mean, Mac territory expensive. Why would we want to spend that sort of money on something that we feel is outdated 12 months later? It doesn't make sense to me.
Incremental upgrades are pretty much perfect in my opinion. Nobody feels forced to upgrade, but the improvements are significant when they do after 2+ years.
And on the other hand, if Apple did make the last model somewhat obsolete each year, we'd all be criticising them for that too.
Phones have matured and that's good. Let the improvements be more in software and services now, the hardware is far beyond what most of us could have imagined when we got our first smartphones. And the fact that Apple continues to give OS updates to older phones demonstrates that, aside from big leaps like M chips and AI, a) the hardware is stellar and b) the main improvements can be delivered via an update.
We can see them more like our ovens, fridges, TVs, iPads, home computers, cars etc, and upgrade them either when they genuinely need replacing or after a more significant period of time than 1-2 years.