That may be true for you but it's not true for many people, like me.
I have twenty years of iPhone data, eg messages, apps, etc. I can't easily move to some other phone.
A desktop, maybe, but I'd still have to repurchase or find alternates to a bunch of software. It is far, far better if the existing system _stays useful_.
>It is far, far better if the existing system _stays useful_
I doubt anyone is arguing the opposite. The point of the parent is that the system staying useful and not turning hostile on your usecase is not under your control or something you can personally prevent, and until that magically changes it's best to structure your use case to be least affected by things not in your control.
"twenty years"? Wasn't the iPhone released in 2007?
I think rounding over 18 years up to 20 is reasonable.