I keep seeing the complaints, but do enough people actually upgrade yearly? Because anecdotally (including online communities in this) I have seen most people claim that they only upgrade every 3-5 years and I think that's sensible as an upgrade cycle and will only get longer now if my own feelings match the general populace.
I personally have found myself needing an upgrade every 3 years on average and think I'll find a way to go longer with phones which don't lose security updates around the exact time the battery starts swelling on my old phone (my previous reason for upgrading and seems to be happening again)
In the US at least, I think most people get their phones through their carrier and are stuck on a contract paying it off for ~3 years. I think rich people and enthusiasts/fanboys are the only ones who upgrade every year or buy it unlocked at full price from the manufacturer.
I am not in the US and not locked into a contract and neither is anyone I know IRL but nonetheless we do upgrade at the same cadence. As for the people who upgrade their phones yearly, unless they're keeping the old phones in a locked box I think it is not that bad if those old phones see use as an upgrade for someone else (either given or sold as a second hand device) or even if those phones run duty as a makeshift device.
I personally think it only becomes a problem if it's literally e-waste or if the majority of people were upgrading yearly (which is again because it'll lead to the first problem but felt like putting it separately too). If it's playing some role in the world it's okay¹ in my book.
^(1: I wonder if people who use their old phones as a secondary device (eg: a music player for running)^) ^(are creating e-waste or not. As in if it would've been better if they used only one device for both purposes and either gave/sold the old phone or didn't buy a new phone in the first place. After all one could make the case that battery degradation would make them need an earlier upgrade)
Most people in the world buys full price from manufacturer. And they are not rich or enthusiasts at all. It's just in the US the consumerist mindset of paying $1500 over 3 years for a $800 phone is enforced by the carriers. And the ones who go out of that mindset to fanboy, buy $1500 overpriced phones. Most people aren't buying flagship phones. Mid and low performance phones are perfectly serviceable for the vast majority of people.