I really don't think they would. If you asked any person on the street what new features came with iOS 11 vs iOS 10 I really don't think they'd be able to tell you. It was a very minor upgrade, and no-one really seemed to care. A number of people I know try to avoid updating because they mostly associate it with a slower phone!
(By its name, High Sierra ought to be an optimization of Sierra also, but its bugginess suggests otherwise.)
Consumers and shareholders like cell phones because they're shiny.
Most people I know are already happy with the functionality of their iOS or Android devices.
https://www.engadget.com/2018/01/23/apple-homepod-no-mutli-r...
"They" already said that when iOS abandoned skeuomorphism, and "they" were damn right. A friend of mine who is not even a tech guy put it very bluntly: "Apple used to change things to make better phones, now they change things to keep up with what others are doing".
Real world objects come in different sizes, so i don’t see what the problem would be in having screens that look like objects having different sizes.
https://gigaom-com.cdn.ampproject.org/ii/w680/s/gigaom.com/w...
How would they look if you squished it for 25%, 50% or 75% split screen view on the iPad? How would it look on the iPad Pros? In landscape? In portrait?
But generally, you can easily have those kinds of design work with any kind of screen dimensions. It won't look completely similar from one size to another, but still look realistic (bigger screen -> bigger objects, or more space between objects).