They have this feature but closing the lid on a MacBook or even putting it to sleep allows Bluetooth devices to stay connected. Heck, a MacBook even while in sleep mode will connect to Bluetooth devices. As far as I can see, this requires a third-party app to fix. Can an application still use the microphone on a Bluetooth device that’s connected?
And you can’t turn bluetooth off without logging in first, a feature which is available for WiFi. Horrendous UX decisions by Apple.
I am not able to disable WiFi from the login screen.
I think it would be a horrendous decision to allow random people to do this.