NavigationStack_bug1.swift

import SwiftUI

enum NavTestRoute: Hashable {
    case child(Int)
}

struct NavTestChildView: View {
    let num: Int

    init(num: Int) {
        print("[init][NavTestChildView]")
        self.num = num
    }

    var body: some View {
        Text("NavTestChildView \(num)")
    }
}

struct NavTestMainView2: View {
    init() {
        print("[init][NavTestMainView2]")
    }
    
    var body: some View {
        VStack {
            NavigationLink {
                NavTestMainView2()
            } label: {
                Text("Reenter NavTestMainView")
            }

            ForEach(1 ..< 10, id: \.self) { num in
                NavigationLink(value: NavTestRoute.child(num)) {
                    Text("Open child \(num)")
                }
            }
        }
        .navigationDestination(for: NavTestRoute.self) { route in
            switch route {
            case let .child(num):
                NavTestChildView(num: num)
            }
        }
    }
}

struct NavTestMainView: View {
    init() {
        print("[init][NavTestMainView]")
    }
    
    var body: some View {
        NavigationStack {
            NavTestMainView2()
        }
    }
}

NavigationStack_bug1_with_binding.swift

enum NavTestRoute: Hashable {
    case child(Int)
}

struct NavTestChildView: View {
    let num: Int

    init(num: Int) {
        print("[init][NavTestChildView]")
        self.num = num
    }

    var body: some View {
        Text("NavTestChildView \(num)")
    }
}

struct NavTestMainView2: View {
    @Binding var items: [Int]

    init(items: Binding<[Int]>) {
        print("[init][NavTestMainView2]")
        self._items = items
    }

    var body: some View {
        VStack {
            NavigationLink {
                NavTestMainView2(items: $items)
            } label: {
                Text("Reenter NavTestMainView")
            }

            ForEach(1 ..< 10, id: \.self) { num in
                NavigationLink(value: NavTestRoute.child(num)) {
                    Text("Open child \(num)")
                }
            }
        }
        .navigationDestination(for: NavTestRoute.self) { route in
            switch route {
            case let .child(num):
                NavTestChildView(num: num)
            }
        }
    }
}

struct NavTestMainView: View {
    @State var items: [Int] = [1, 2, 3, 4]

    init() {
        print("[init][NavTestMainView]")
    }

    var body: some View {
        NavigationStack {
            NavTestMainView2(items: $items)
        }
    }
}

NavigationStack_bug1_with_binding2.swift

import SwiftUI

enum NavTestRoute: Hashable {
    case child(Int)
}

struct NavTestChildView: View {
    let num: Int

    var body: some View {
        Text("NavTestChildView \(num)")
    }
}

struct NavTestMainView_Control: View {
    let num: Int
    let isDetailMode: Bool
    @Binding var items: [Int]

    var body: some View {
        VStack {
            if isDetailMode {
                Text("Long mode \(num)")

                ForEach(items, id: \.self) { item in
                    NavigationLink(value: NavTestRoute.child(item)) {
                        Text("Go to \(item)")
                    }
                }
            } else {
                Text("Short mode \(num)")
            }
        }
    }
}

struct NavTestMainView2: View {
    @State var items: [Int] = []

    var body: some View {
        ForEach(1 ..< 5) { num in
            NavigationLink {
                NavTestMainView_Control(num: num, isDetailMode: true, items: $items)
            } label: {
                NavTestMainView_Control(num: num, isDetailMode: false, items: $items)
            }
            .task {
                items = [1, 2, 4]
            }
            .navigationDestination(for: NavTestRoute.self) { route in
                switch route {
                case let .child(num):
                    NavTestChildView(num: num)
                }
            }
        }
    }
}

struct NavTestMainView: View {
    init() {
        print("[init][NavTestMainView]")
    }

    var body: some View {
        NavigationStack {
            NavTestMainView2()
        }
    }
}

поменял на extension Binding: Equatable where Value: Hashable { иначе ломается .searchable