I navel-gaze that if we redesigned communications from the ground up we could handle this better. When you greet someone physically you can add each other as known trusted contacts immediately. And when you sign up to some service online and have to put in your contact info, which likewise prompts you to add them as contact. And you can't share along a contact you know to someone else without that contact ID uniquely identifying you.
That way, everyone who should contact you can do so and if someone else gets their hand on your contact info you can figure out who leaked it.
That way, everyone who should contact you can do so and if someone else gets their hand on your contact info you can figure out who leaked it.