[Analemma_]

Yeah, macOS development is in a tricky spot at the moment: Apple has signaled that SwiftUI is the future, and so starting out with ObjC/Cocoa is making yourself obsolete right from the get-go, but SwiftUI is not production-ready yet and doing anything serious with it is difficult if not impossible.

Presumably in a few more years the wrinkles will be ironed out of SwiftUI, but right this instant is unfortunately a crummy time to start out with Mac development. I would also agree that you should start with SwiftUI, but just with the awareness that it sucks ass and that you'll have to throw out most of what you write over the next few years.

[kitsunesoba]

I wouldn't worry too much about AppKit going anywhere any time soon. It's probably in a similar position to where Objective-C is, where it's not receiving a whole lot of additions/iterations, but it'll stick around for years to come because of how much of the OS and how many third party apps still rely on it. It's a good idea to become familiar with SwiftUI but I think Cocoa is in a much better position than say Carbon was several years ago.