Seems like the easiest fix would be to mandate the same charging cable for all phones (no dongles) and user replaceable batteries that require no tools to change.
With those two simple tweaks it would be much easier to keep a phone for 3 or more years. My google pixel seems like it could easily last for many years with it's quad core, 128GB storage, 4GB ram, and 2560x1440 display. Lets be honest, for most uses that's plenty for many years to come.
But already the battery is not as good as it was new and it's only going to get worse.
With those two simple tweaks it would be much easier to keep a phone for 3 or more years. My google pixel seems like it could easily last for many years with it's quad core, 128GB storage, 4GB ram, and 2560x1440 display. Lets be honest, for most uses that's plenty for many years to come.
But already the battery is not as good as it was new and it's only going to get worse.