That sounds terrifying
Seems like incredibly poor market fit.
I'm told there was even a time when the number only addressed a location, so you would have to figure out who was talking on the other end through a complex linguistic handshake.
And it didn't even have identity authentication, past a basic voiceprint!
I hear there's some way you can use an app on your phone to have a voice conversation with someone else, but apparently you need to know a magic number?