This effect has been compounding too. I used to upgrade almost every cycle but have been on 11 Pro now and haven't been motivated to upgrade until this 16. It takes the combined changes of about 4 cycles to match the level of interest in upgrading single cycles did in the first 10 years.

If I do get a 16 Pro the only thing I can even think of from an upgrade perspective that would make it last less than 5 years would be if on device inference becomes a major thing and there are huge and relevant improvements, everything else is basically mature and I can't see being motivationally better in a few years.

People bring up battery as a big thing for upgrading but with the smarter charging that has changed a lot, my 11 Pro is still at 80% max after 4+ years which isn't materially different on a day to day basis for me.