Navigation bar issues on watchOS 7 Beta 6

I'm trying out the new NavigationView in watchOS 7 and having some issues with the navigation bar not showing up in child views.

Example

Code Block swift
import SwiftUI
struct ContentView: View {
    var body: some View {
        NavigationView {
            NavigationLink(
                destination: DestinationView(),
                label: {
                    Text("Destination")
                })
                .navigationTitle("Root")
        }
    }
}
struct DestinationView: View {
    var body: some View {
        NavigationView {
            Text("I'm here!")
                .navigationTitle("Destination")
        }
    }
}

Test setup

• macOS 11.0 Beta 5

• watchOS 7.0 Beta 6

• Xcode 12.0 Beta 6

When running the app in the simulator or on the watch, the root view correctly displays the navigation bar, while the destination view does not.

Confusingly, the Xcode live preview does the opposite: The root view is missing the navigation bar, but the destination view is showing both the title and back button correctly.

The only mode in which the navigation bar is visible in both views is if I from Xcode select Preview on Device.

I'm new to SwiftUI and though I'm leaning toward this being a bug with the beta, I thought I'd check here to make sure I'm not just doing it wrong.