Apple believes SwiftUI is the future, not AppKit and UIKit/Cocoa.
Sure, Apple positions SwiftUI as its primary forward-looking UI framework, but AppKit and UIKit still developed and have access to all API that SwiftUI has.
alt Hacker News
Sure, Apple positions SwiftUI as its primary forward-looking UI framework, but AppKit and UIKit still developed and have access to all API that SwiftUI has.