An average lifespan of about for years is just huge, even if this probably is pushed a lot by Macs having a longer lifespan than phones..
On the other hand, my mother still uses the iPhone 4S I handed down to get than I got my 6.
Considering how many fans that machine has, I’d say that’s quite good. Fan failures in the Dell machines I’ve dealt with over the years are practically guaranteed within three to four years.
We also know the iPad tends to have a much longer lifecycle than the phone. If it wasn’t for the lack of updates and new software many people would still be using the iPad 2 from 2012 (?).