Strange navigation with NavigationStack inside NavigationSplitView

Question

Why does "Above NavigationStack" disappear when I click "Nav Link"?

struct ContentView: View {
    var body: some View {
        NavigationSplitView {
            // Sidebar content irrelevant
        } detail: {
            Text("Above NavigationStack")
            NavigationStack {
                NavigationLink("Nav Link") {
                    Text("Linked page")
                }
            }
        }
    }
}

When I remove NavigationSplitView the behavior changes. I am compiling for macOS 13.3.1 (a) with Xcode 14.3.