[propogandist]

Most people aren't walking around with one time phone numbers, they have a phone number that's shared by family, friends and co-workers that will consistently resolve to the same individual whenever someone wants to connect.

Being a unique number that is tied to a single individual, it can function as a proxy for identity. This, obviously, assumes you are operating like the average user.

[marcosdumay]

There are plenty of attacks where some random person can get hold of any phone number for a few seconds. It is not a proxy for identity, as it's available on demand for the exact people trying to impersonate you.

[lone_haxx0r]

Regular people don't "have" or control any phone number, telcos do.