Earlier quoted context omitted.
Closer to every 5-6 years these days and with ram prices going up it will be even longer. Especially with the low/mid range phones, which are most phones outside some developed countries, people will keep their phones as long as they can.
I mean are there even any reasons to buy a new phone? If I compare the Pixel 6 Pro I'm using at the moment to current models, they are functionally identical. The only reason to upgrade might be getting a fresh battery and access to firmware updates. Otherwise I'd be happy to continue using it for the next 10 years.
I swear a midrange Chinese phone from 2017 would be enough for me in 2026 to read HN/Whatsapp and some Youtube.