I've had an iPhone since 2009 and I'm definitely familiar with the "time traveling" effect of upgrading phones, but I think it has diminished a lot as the technology has matured.
I've been using a 6S since 2015 (this thread caught my interest because it's now somewhat of a Ship of Theseus as I've replaced so many parts over the years), but the 11 Pro I bought last year was the first time a multi-year-gap upgrade felt rather incremental, especially for $1100. I returned it and expect to continue to use and repair the 6S until they drop iOS support for it.
I've been using a 6S since 2015 (this thread caught my interest because it's now somewhat of a Ship of Theseus as I've replaced so many parts over the years), but the 11 Pro I bought last year was the first time a multi-year-gap upgrade felt rather incremental, especially for $1100. I returned it and expect to continue to use and repair the 6S until they drop iOS support for it.