Hehe yeah, same when I think about it… I guess best thing to do is buy on launch and update every 2-5 years.
So owning a device for 6 years between age 1 and 7 will generally have a lower cost than owning a device between age 0 and 6.
For Apple products it’s generally feasible to effectively buy first hand devices aged 1+ because they’re still available for sale (at least in some retailers) after a new edition is released.