Apple has not abandoned Objective C. It still has first class support on all their platforms, and the vast majority of their OS frameworks and applications are developed in ObjC. Swift is growing as an internal tool, but it’s nowhere near even 50% of the 1st party code on a mac or iphone.
Improvements have slowed on ObjC, as Apple’s focus switched to swift - ObjC 2.0 in 2014 was the last major change.
> The Objective-C language, AppKit & UIKit frameworks, and Interface Builder have empowered generations of developers. These technologies were built for each other, and will continue to serve us well for a long time to come, but over time new abstractions become necessary. For a while now, you've seen us hard at work defining the next generation of integrated language, frameworks, and tools: Swift, SwiftUI, and Xcode Previews.
> Tight integration in a development platform like this requires that all three pieces be designed and evolved together, both driving and driven by one another. Swift result builders were inspired by SwiftUI's compositional structure. SwiftUI's declarative views were enabled by Swift value types. And Xcode Previews was specifically designed for, and enabled by, both. Now, the result is the best development platform that we have ever built. And this year, Swift, SwiftUI, and Xcode all have fantastic updates that take this vision further, and make it even easier for you to build great apps for all of our platforms. And it all starts with Swift.
Only when Apple comes out with a flagship app written in Swift (I would require SwiftUI too, but I don’t want to be that cruel…) will I entertain the idea that ObjC can be replaced. If they were eating their own dogfood internally, they should be aware that it is nowhere near ready for AAA app development.
A complete platform used by millions of people, and apparently has saved several lives as per this week's announcement, doesn't count as flagship, got it.
Improvements have slowed on ObjC, as Apple’s focus switched to swift - ObjC 2.0 in 2014 was the last major change.