Why does my NavigationView bounce back to its initial view?

Question

I'm trying to create a programmatically-driven view navigation with SwiftUI 2 with an environmentObject that is used to store the selection of the current view in a NavigationView.

I'm aware the below code navigation could simply work with only navigation links directly but my actual code is more complex and views will have to be navigated based on receiving a network response among possibly other mechanisms and I want to create a clear and unified navigation logic for this so I'm trying to use the currentView property in the environment object.

ContentView:

import SwiftUI

enum NavigationViewTarget: String {
    case ContentView
    case RegistrationView
    case LoginView
    case LandingView
}

final class GlobalViewModel: ObservableObject {
    @Published var currentView: NavigationViewTarget? = .ContentView
}

struct ContentView: View {
    @StateObject var viewModel = GlobalViewModel()
    
    var body: some View {
        GeometryReader {
            screen in
            
            NavigationView {
                ScrollView(showsIndicators: false) {
                    VStack(alignment: .leading) {
                        HStack {
                            NavigationLink(destination: RegistrationView(), tag: .RegistrationView, selection: $viewModel.currentView) { EmptyView() }.hidden()
                            NavigationLink(destination: LoginView(), tag: .LoginView, selection: $viewModel.currentView) { EmptyView() }.hidden()
                            Button(action: { viewModel.currentView = .RegistrationView }) {
                                Text("Register")
                            }
                            Button(action: { viewModel.currentView = .LoginView }) {
                                Text("Login")
                            }
                        }
                    }
                }
                .navigationViewStyle(StackNavigationViewStyle())
            }
        }
        .environmentObject(viewModel)
    }
}

RegistrationView:

import SwiftUI

struct RegistrationView: View {
    @EnvironmentObject var viewModel: GlobalViewModel
    
    var body: some View {
        GeometryReader {
            screen in
            
            ScrollView(showsIndicators: false) {
                VStack(alignment: .leading) {
                    HStack {
                        NavigationLink(destination: LandingView(), tag: .LandingView, selection: $viewModel.currentView) { EmptyView() }.hidden()

                        Button(action: { viewModel.currentView = .LandingView }) {
                            Text("Submit")
                        }
                    }
                }
            }
        }
    }
}

LandingView:

struct LandingView: View {
    @EnvironmentObject var viewModel: GlobalViewModel
    
    var body: some View {
        Text("Landing View")
    }
}

LoginView:

import SwiftUI

struct LoginView: View {
    @EnvironmentObject var viewModel: GlobalViewModel
    
    var body: some View {
        Text("Login View")
    }
}

The app navigates to RegistrationView and when tapping the Submit button in it it navigates to LandingView but then automatically bounces back to ContentView. Any ideas why this happens?