ContentView.swift

struct ContentView: View {
    var body: some View {
        VStack {
            StateViewA()
            StateViewB()
            StateViewC()
            StateViewD()
        }
    }
}

class StateHolder: ObservableObject {
    var state = State()
}

class State: ObservableObject {
    @Published var value = 0.0
}

struct StateViewA: View {
    @StateObject var state = State()
    
    var body: some View {
        print("A body refresh")
        return Slider(value: $state.value)
    }
}

struct StateViewB: View {
    @StateObject var stateHolder = StateHolder()
    
    var body: some View {
        print("B body refresh")
        return Slider(value: $stateHolder.state.value)
    }
}

struct StateViewC: View {
    @StateObject var state = State()
    
    var body: some View {
        print("C body refresh")
        return ControlView(value: $state.value)
    }
}

struct StateViewD: View {
    @StateObject var stateHolder = StateHolder()
    
    var body: some View {
        print("D body refresh")
        return ControlView(value: $stateHolder.state.value)
    }
}

struct ControlView: View {
    @Binding var value: Double

    var body: some View {
        print("Control View refresh")
        return Slider(value: $value)
    }
}