True, but it's important to note phone numbers have the amount of security as e-mail/SMTP for self-identification. That's why it's so easy to spoof phone number

True, but it's important to note phone numbers have the amount of security as e-mail/SMTP for self-identification. That's why it's so easy to spoof phone numbers and how robo-callers work. Only this year, telecos are finally adding signature verification to caller-ID/reverse lookups. Once every teleco in a given country supports and is required to implement phone number verification, there will be a higher degree of assurance a phone number on your caller ID really is the person calling, but it's not there yet.