Well, I'd disagree with the first statement having worked with IPX/SPX ;-)
But, yeah, you're not wrong for IP networking - however, an app on the phone could forward the MAC address of the bluetooth connected device.
But, yeah, you're not wrong for IP networking - however, an app on the phone could forward the MAC address of the bluetooth connected device.
But you are correct that regular apps can't address the MAC address of connected Bluetooth devices, so the tracking vulnerability that OP is suggesting isn't really possible.