> Most people I know only get new phones because their battery will no longer get them through the day

I don't disagree with this, but I also think it's because the battery often dies around the time most people would consider upgrading anyway. The battery isn't the only reason people upgrade, it's just a forcing factor.

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 still think we're going to see people upgrading around the 3-5 year mark. I would point to the current market as evidence of this. An iPhone battery replacement is somewhere between $50-$100 right now which is drastically cheaper than a new iPhone and yet we still see the 3-5 year upgrade cycle. Maybe making it something you can do at home in a few minutes will result in a few more people just choosing to replace the battery vs the entire phone, but I don't see it drastically changing things since a cheap alternative to replacing the phone already exists and yet we still see the 3-5 year replacement cycle.

I can't speak to the experience with Android but Apple offers both in-store battery replacement or Mail-in battery replacement for $70-120 which to me seems very reasonable. Could it be cheaper? Sure, maybe I guess? But $70-120 is a lot less than a new phone. And this way we don't need to compromise the shell of the phone with seams and things that can fail.

https://support.apple.com/iphone/repair/battery-replacement

It would seem that "different opinions are out there" is not really a good basis for "one opinion enforced by EU directive", though.

It's now possible to carry a spare battery or two, instead of lugging a portable power bank and slowly charging your phone. This is great news for outdoorsy types, travel, long bicycle rides, hiking, and so on.

> They hate having to set up a new phone when their old one is totally fine other than the battery.

That is why I have the battery replaced every few years.

> Most people I know only get new phones because their battery will no longer get them through the day.

Most people I know get a new phone when they can't take the cracked screen anymore, or when they completely lose the phone. Or because a pretty new one came out and they upgraded two years ago so it's "time". That's most people.

> Most people I know only get new phones because their battery will no longer get them through the day

Getting the battery replaced is already trivial and cheap. Revealed preference is that most people say they want it, but don't. This won't even decrease the cost or difficulty (you'll still need a screwdriver).

Even going directly to Apple for out-of-warranty battery replacement is almost always way cheaper than getting another phone.

Most people I know get a new phone because the marketing works on them and they lie that it's about the battery.

They all know about Apple's battery replacement programme that's been around for years now

And iCloud backups makes setting up a new phone trivial

> Most people I know only get new phones because their battery will no longer get them through the day.

I am not sure if your statistic is correct or people giving you excuses to get the latest model. If we speak iphones, flipping the battery is cheap and fast process, incomparable with the hassle of doing re-setup.

I am not sure if the process is equally or more simple with android phones though, but in my circle noone buys new phone because of the battery (often the battery is used as excuse to get a newer model).