I like this idea a lot, and I'm just now remembering that there at least used to be a mod that basically did this. Don't know if it's been updated at all--it was from before stories or even the eco-living style texts were a thing yet--but I for one would greatly welcome this mechanic into the main game.
As an addition, maybe there could also be a function to ask for someone else's number? That could be a way, for instance, for sims to get in contact with other sims without necessarily "meeting" them. A parent could get the numbers of their kids friends, a kid could get the number of their friend's parents, sims who were dating could give their SO the contact info of their siblings or roommates, ect ect ect. (And then our sim could invite them over or throw an event with them on the guestlist without having to awkwardly stalk them and make introductions themselves lol.)
