So if most iPhone users are using these buttons to disconnect from their current network, or to disconnect the current bluetooth device, then I understand why they'd change them to have that meaning.
Disconnecting from the current wifi network or disconnecting the current bluetooth device probably comes up somewhat frequently as a task the user wants to accomplish, whereas actually disabling the radios likely does not come up much at all outside of airplane mode. So I get what Apple is doing. I wonder why they chose to maintain the button UI though. Perhaps it's because people are expecting it, and are used to it?