Aren't phones supposed to get cheaper every year?
Like a Gucci handbag or a Rolex watch. With a smaller markup.
After the 2 year mark our Android phones are literally in the junk drawer, and her iPhone 6s is still functioning as fast as the day it was purchased.
Recently the battery got swollen, I took it to an apple shop and got a replacement (a refurbished iPhone 5) for 100 dollars.
I've had nothing but bad experiences with iPhones in the first 4 years they existed, and have switched back to android for the past 6.
There are always a few Android devices that get multiple OS upgrades, but you can't predict which one of the current generation is the update-unicorn.
As for a 2 year shelf life - I'm still on a 2013 Nexus 5. It runs smooth and runs everything I need. Isn't a 6s only 2 years old?