I don't think his phone system analogy is correct. Yes, you can pick up any phone and make a call, but you can't receive a call to 'your' number from any phone.

I don't think his phone system analogy is correct. Yes, you can pick up any phone and make a call, but you can't receive a call to 'your' number from any phone. i.e. there is still state associated with the phone network, and landlines are not portable in the same sense that mobiles and laptops are.