> If batteries normally last 3-5 years, I don't think we're going to start seeing most people keep their phones for 7-10 years.

I think they will eventually. People hang on to their computers for longer and longer because old ones are just good enough. Phones are getting to that same stage in their evolution where they stopped evolving by leaps and bounds between generations. A seven year old phone like an iPhone 11 for example is perfectly adequate for a lot of people.

There are two real blockers from keeping a phone for so long, official software support and battery life. If some big manufacturers solved the first with extended support cycles, which is an expensive one, why not solve the second too?

The second problem is already solved though. My wife just had to get her phone iPhone battery replaced so we went to the Apple store and it was $99 and the replacement took less than an hour.

The average person probably can't (or won't) replace an iPhone battery themselves right now, but getting an iPhone battery replaced is relatively easy and cheap compared to replacing the phone and yet most people still don't do it.

I feel people on here are forgetting that for a lot of people a phone is not just about utility. It's a lifestyle purchase that people tie into their self identity. That's why we see things like the whole blue bubble vs green bubble messaging drama that came up a few years ago.