all they need to do is be in the approximate region of the cell signal through triangulation to figure out the phone numbers / unique identifiers attached to the phone.

then its a matter of time before they link real identity to the phone. With the wide availability of femtocells, all they need to do is get lucky once.

This puts operators of Signal proxies at potential harms way! Absolutely irresponsible for people on HN to downvote and downplay genuine security concerns.