Is that a lot? I'm still using an iPhone 11 and honestly don't see a reason to upgrade. My friends who use iPhones are rocking the old ones that are round at the sides. Yet on public transport etc I see iPhone 14's everywhere. Buying a new phone every year or every other year is cringe imo.
For me, I'm on a 13 Pro. If the 15 didn't have USB-C, I'd probably have skipped the iteration. Since there's USB-C and most likely WiFi-6e support, and I play MOBAs on the iPhone that are sensitive to latency and have WiFi-6e APs, it's reason enough for me to upgrade.
I only recently started getting annoyed at how sluggish apps have felt compared to using my friends' newer phones.
There is a set of people (like a friend I have) who doesn't like using cases and feel that the point of having a case-less phone is that the phone is meant to be shown off in its bare glory.
But I will end up wearing out the oleophobic coating on the screen and the battery will no longer last a full day
Also the battery typically will no longer last a full day.