Comment by jeroenhd

Some devices come with apps that include proprietary renaming features. Those devices can be renamed.

Your iPhone's rename feature won't change anything for other devices. Maybe Apple is smart enough to sync the renamed device to other Apple devices as well, I don't know about that, but it certainly won't change what the other passengers on your phone see.

You can distinguish Bluetooth devices by their MAC address, that's usually how the rename mapping works.