I still use a 5 year old Apple Watch because there have been no new features worth spending a dollar for.
Comparing my current phone (14 pro max) against a phone two generations ahead... nothing is really enticing me to upgrade. Summarized notifications using apple intelligence is nice, but not worth $1500
https://www.apple.com/ca/iphone/compare/?modelList=iphone-14-pro-max,iphone-16-pro-max,iphone-16-pro
Discussion
I got a watch ultra earlier this year and I’ll only upgrade when the battery is bad