The padding at the bottom appears to be caused by the Home Indicator. However, I found a workaround by applying the padding to the background Color instead. Please see the updated code below. Screenshots are attached for your reference.

struct ContentView1: View {
    var body: some View {
        TabView {
            ForEach(0...10, id: \.self) { page in
                ZStack {
                    Color(.blue).opacity(0.2)
                        .padding(.bottom, -20)

                    Text("Page \(page)")
                }
                .edgesIgnoringSafeArea(.all)
            }
        }
        .tabViewStyle(.page)
    }
}

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