In iOS 12 and 13, up to 13.4, few lines of codes:
navigationController?.navigationBar.isTranslucent = false
navigationController?.navigationBar.barTintColor = .black
navigationController?.navigationBar.tintColor = .red
allow to hide the status bar under the navigation bar.
With swiftUI is perhaps even simpler
.statusBar(hidden: hideStatusBar)
but it requires to rewrite the whole app from storyboard to swiftUI.
Hiding the status bar, or go to full screen, is still be possible without using swiftUI on legacy code?