Focus a TextField in SwiftUI seems not to work

I want to use the newly presented ability to focus on something in SwiftUI, in my case a TextField where the user should input something:

struct MyView: View {
    @State var name: String = ""
    @FocusState private var nameIsFocused: Bool
    
    var body: some View {
        Form {  
            TextField("Name", text: $name).focused($nameIsFocused)
        }
        .onAppear {
            nameIsFocused = true
        }
    }
}

For some reason this is not working. Any Idea why? I don't get the focus when entering the view.