StateObject alternative on iOS 13 / macOS Catalina

StateWrappedView.swift

import SwiftUI

protocol ViewModelContainable: View {
    
    associatedtype ViewModel : ObservableObject
    
    init(model: ViewModel)
}

// This struct is a direct MVVM alternative to @StateObject in iOS 14 and Mac OS Big Sur.
struct StateWrapped<U: ViewModelContainable, T> : View
    where U.ViewModel == T
{
    @State var model: T
    
    var body : some View {
        U(model: model)
    }
}

If you just want a propertyWrapper that simply replaces @StateObject: https://gist.github.com/Amzd/8f0d4d94fcbb6c9548e7cf0c1493eaff