This is a fair point, but from what I've seen from Swift UI these optimisations are already happening. Lists used to be backed by UITableViews in all contexts

This is a fair point, but from what I've seen from Swift UI these optimisations are already happening. Lists used to be backed by UITableViews in all contexts I believe. Now, if I remember rightly, they are backed by a mix of UICollectionView and raw combinations of views depending on various factors like the number of elements or whether that number changes. These sorts of changes didn't go super smoothly, I think iOS 13.0 was the first one with SwiftUI, then 13.3 changed a lot of the under the hood details and broke some things (we had 13.2/3 specific hacks), but since iOS 14 things have been much more stable and there have been fewer breakages.