I noticed that in iOS 11 on the iPhone you can still completely turn off Wi-Fi without opening the settings. I just have to ask Siri about it.
He told this to his wife and then the following dialogue took place:
Wife: Turn off the internet.
Siri: I don’t know how to do it.
I: I have to ask polently.
Wife: Siri, please turn off this fucking Wi-Fi.
Siri: Okay, Wi-Fi settings are turned off.