This is great, thank you!
Quick follow-up. I want to persist the selected value in scene storage. Before typing this up, I was doing that by replacingContentView's @State with @SceneStorage('selectedValue'). While that stored it, it still had the "updating the default does nothing" problem.
Is it safe to assume that, now that I'm in the realm of ObservableObject that I need to write my own state storage and restoration, rather than use something like @SceneStorage?