As the world has grown more interconnected, the actual value of people's identifying information has sharply risen (as has the availability of it), but we haven

As the world has grown more interconnected, the actual value of people's identifying information has sharply risen (as has the availability of it), but we haven't figured out how to adjust our expectations for it. We still use a bunch of bits of fairly small data as high-value sources of information. In the US, social security numbers were not intended as a unique or unguessable ID, especially since they used to be (still are?) given in ranges to facilities for births/etc, so knowing their birthdate and where they were born let you drop a bunch of possible values. An even better example of uncontrolled information value, to me, is phone numbers. We used to, with few exceptions, list publicly people's land phone numbers in regional books, unless they opted out. Now, increasing numbers of people don't have land lines, we don't have a public cell phone number <-> name mapping (though it often leaks through other public information sources), and worst of all...since we've started using phone numbers as both an "in case of emergency contact here" for account lockout, and as a 2FA source (either SMS or actual calls), and these networks were not designed with robust security guarantees in mind, just knowing your phone number can be sufficient to forge a SIM card to hijack the number. [1] But not giving out your phone number defeats the entire point of having it, and we have not yet convinced most institutions to stop using phone numbers as reliable contact endpoints, so what's to be done? [1] - https://motherboard.vice.com/en_us/article/vbqax3/hackers-sim-swapping-steal-phone-numbers-instagram-bitcoin https://motherboard.vice.com/en_us/article/vbqax3/hackers-si...