NavigationSplitView doesn't work using enum with associated type

I have the following model in place for navigating to various pages:

enum Destination: Hashable {
  case today
  case activity
  case settings(path: SettingsPath? = nil)
  case project(project: ProjectItem? = nil)
  
  enum SettingsPath: Hashable {
    case cycles
    case donations

  }

}

In an ObservableObject, I'm using

@Published var sidebarDestination: Destination? = .today

And then in various NavigationLink buttons, I'm using the following initializer -

 NavigationLink(value: NavigationModel.Destination.activity...

In the detail section of my NavigationSplitView I'm using a switch like so

detail: {
      if let destination = navigationModel.sidebarDestination {

        switch destination {
        case .today:
            TodayView()
        case .project(let project):
          // FIXME: Why is the detail view not updating?

            if let selectedProject = project {
              ProjectDetailView(project: selectedProject)
            } else {
              EmptyView()
            }
...

I've noticed that the pages with an enum case with an associated value are not updating correctly - the title on the page will update, but none of the other content. The pages with an enum case without an associated type seem to work just fine.

All of this is using an iPad - the larger screen sizes

Is this a bug?