RemoveStatusBarForiOSAppsOnMacWithSwiftUI.swift

import SwiftUI

@main
struct MyApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
                .statusBar(hidden: ProcessInfo.processInfo.isiOSAppOnMac)
        }
    }
}

RemoveStatusBarForiOSAppWithoutSwiftUI.swift

class MyViewController {
    // ...
    override var prefersStatusBarHidden: Bool {
        if super.prefersStatusBarHidden { return true }
        if #available(iOS 14.0, *) {
            return ProcessInfo.processInfo.isiOSAppOnMac
        }
        return false
    }
}