For new iOS apps you can select Swift or Objective-C but you cannot choose Objective-C for new watchOS apps.
A new watchOS app is always Swift.
Any help would with selecting Objective-C for new watchOS apps would be greatly appreciated.
Cannot select Objective-C in Xcode 16.1 for new watchOS app
New watchOS apps are built with SwiftUI for the UI layer, as well as the associated app lifecycle model. Building interfaces with SwiftUI requires Swift, and using techniques like storyboards for watchOS, which were based on Objective-C frameworks, was deprecated in watchOS 7 (the Xcode 14 Release Notes mentions this).
— Ed Ford, DTS Engineer