I found the same issue when testing with SwiftUI tutorial - creating a watchos/macos app.
I can't get away with the error
The run destination iPhone 12 Pro Max is not valid for Running the scheme 'WatchLandmarks'. anyway even when only WatchKitExtension is selected as the target.
It only happens to the watchos scheme, but not the macos scheme. This seems to be a defect of XCode Previews.
BrianZhang
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